Analysts and Investors Day June 2017 Main Street Capital - - PowerPoint PPT Presentation

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 1

Analysts’ and Investors’ Day

June 2017

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 2

Disclaimers

Main Street Capital Corporation (MAIN) cautions that statements in this presentation that are forward-looking, and provide other than historical information, involve risks and uncertainties that may impact our future results of operations. The forward-looking statements in this presentation are based on current conditions as of June 8, 2017 and include statements regarding our goals, beliefs, strategies and future operating results and cash flows, including but not limited to the amount of leverage available to us and the five year strategic overview. Although

• ur management believes that the expectations reflected in any forward-

looking statements are reasonable, we can give no assurance that those expectations will prove to have been correct. Those statements are made based on various underlying assumptions and are subject to numerous uncertainties and risks, including, without limitation: our continued effectiveness in raising, investing and managing capital; adverse changes in the economy generally or in the industries in which

• ur portfolio companies operate; changes in laws and regulations that

may adversely impact our operations or the operations of one or more of

• ur portfolio companies; the operating and financial performance of our

portfolio companies; retention of key investment personnel; competitive factors; and such other factors described under the captions “Cautionary Statement Concerning Forward Looking Statements” and “Risk Factors” included in our filings with the Securities and Exchange Commission (www.sec.gov). We undertake no obligation to update the information contained herein to reflect subsequently

• ccurring

events

• r

circumstances, except as required by applicable securities laws and regulations. This presentation is neither an offer to sell nor a solicitation of an offer to buy MAIN’s securities. An offering is made only by an applicable

• prospectus. This presentation must be read in conjunction with a

prospectus in order to fully understand all of the implications and risks of the offering of securities to which the prospectus relates. A copy of such a prospectus must be made available to you in connection with any

• ffering.

The summary descriptions and other information included herein are intended only for informational purposes and convenient reference. The information contained herein is not intended to provide, and should not be relied upon for, accounting, legal or tax advice or investment

• recommendations. Before making an investment decision with respect to

MAIN, investors are advised to carefully review an applicable prospectus to review the risk factors described therein, and to consult with their tax, financial, investment and legal advisors. These materials do not purport to be complete, and are qualified in their entirety by reference to the more detailed disclosures contained in an applicable prospectus and MAIN’s related documentation. No representation or warranty, express or implied, is made as to the accuracy or completeness of the information contained herein, and nothing shall be relied upon as a promise or representation as to the future performance of MAIN. Distributable net investment income is net investment income, as determined in accordance with U.S. generally accepted accounting principles,

• r

U.S. GAAP, excluding the impact

• f

share-based compensation expense which is non-cash in nature. MAIN believes presenting distributable net investment income and the related per share amount is useful and appropriate supplemental disclosure of information for analyzing its financial performance since share-based compensation does not require settlement in cash. However, distributable net investment income is a non-U.S. GAAP measure and should not be considered as a replacement for net investment income and other earnings measures presented in accordance with U.S. GAAP. Instead, distributable net investment income should be reviewed

• nly

in connection with such U.S. GAAP measures in analyzing MAIN’s financial performance.

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 3

A Differentiated Approach

Invests in the under-served Lower Middle Market (LMM)

• Generally companies with revenue between $10 million - $150

million; EBITDA between $3 million - $20 million Equity investments are key component of LMM portfolio

• Have contributed to our 75% growth (6.2% CAGR) in net asset

value (NAV) since 2007

• Generate dividend income and realized gains to support dividend

growth Internally-managed operating structure

• Provides cost efficient model with significant operating leverage
• Alignment of interests between management and shareholders

Attractive asset management advisory business Significant management ownership / investment in MAIN Strong capitalization and liquidity position – stable, long-term debt and significant available liquidity to take advantage of

• pportunities
• Favorable opportunities in capital markets through investment

grade rating of BBB from Standard & Poor’s Rating Services

• Total liquidity of $335 million at June 2, 2017(1)

Focus on Lower Middle Market, hybrid debt and equity investment strategy and internally managed

• perating structure

differentiate MAIN from

• ther investment firms

(1) Includes undrawn portion of debt capital, including $109.8 million of remaining SBIC debenture capacity

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 4

Lower Middle Market (LMM) Investment Strategy

Investment Objectives

• High cash yield from secured debt investments (10.9% weighted

average cash coupon as of March 31, 2017); plus

• Capital gains and cash dividends from equity investments

Investments are structured for (i) protection of capital, (ii) high recurring income and (iii) meaningful capital gain opportunity Focus on self-sponsored “one stop” financing opportunities

• Partner with business owners, management teams and

entrepreneurs

• Provide highly customized financing solutions
• Recapitalization, buyout, growth and acquisition capital
• Extensive network of grass roots referral sources
• Strong and growing “Main Street” brand recognition / reputation

Investments have low correlation to the broader debt and equity markets and attractive risk-adjusted returns LMM investment strategy differentiates MAIN from its competitors and provides attractive risk- adjusted returns

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 5

LMM Investment Opportunity

Large and critical portion of U.S. economy

• 175,000+ domestic LMM businesses (1)

LMM is under-served from a capital perspective and less competitive Inefficient asset class generates pricing inefficiencies

• Typical entry enterprise values between 4.5x – 6.5x EBITDA
• Typical entry leverage multiples between 2.0x – 3.5x EBITDA to

MAIN debt investment Partner relationship with the management teams of our portfolio companies vs a “commoditized vendor of capital” MAIN targets LMM investments in established, profitable companies Characteristics of LMM provide beneficial risk- reward investment

• pportunities

(1) Source: U.S. Census 2012 – U.S. Data Table by Enterprise Receipt Size; 2012 County Business Patterns and 2012 Economic Census; includes Number of Firms with Enterprise Receipt Size between $10,000,000 and $99,999,999

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 6

LMM Investment Portfolio

73 portfolio companies / $886.6 million in fair value

• 45% of total investment portfolio at fair value

Debt yielding 12.2% (68% of LMM portfolio at cost)

• 96% of debt investments have first lien position
• 74% of debt investments earn fixed-rate interest
• Over 800 basis point net interest margin vs “matched” fixed

interest rate on SBIC debentures Equity in 99% of LMM portfolio companies representing 37% average ownership position (32% of LMM portfolio at cost)

• Opportunity for fair value appreciation, capital gains and cash

dividend income

• 56% of LMM companies(1) with direct equity investment are

currently paying dividends

• Fair value appreciation of equity investments supports Net Asset

Value per share growth

• Lower multiple entry valuations, lower cost basis
• $115 million, or $2.07 per share, of cumulative pre-tax net

unrealized appreciation at March 31, 2017 LMM Investment Portfolio consists of a diversified mix of secured debt and lower basis equity investments

(1) Includes the LMM companies which (a) MAIN is invested in direct equity and (b) are treated as flow-through entities for tax purposes; based upon dividend income for the trailing twelve month period ended March 31, 2017

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 7

LMM Investment Portfolio

Median LMM portfolio credit statistics:

• Senior leverage of 2.8x EBITDA to MAIN debt position
• 2.6x EBITDA to senior interest coverage
• Total leverage of 3.2x EBITDA including debt junior in priority to

MAIN

• Free cash flow de-leveraging improves credit metrics and

increases equity appreciation Average investment size of $10.6 million (less than 1% of total investment portfolio) Opportunistic, selective posture toward new investment activity

• ver the economic cycle

High quality, seasoned LMM portfolio

• Total LMM portfolio investments at fair value equals 115% of cost
• Equity component of LMM portfolio at fair value equals 165% of

cost

• Majority of LMM portfolio has de-leveraged and experienced

equity appreciation – 45 LMM portfolio companies with net unrealized appreciation

• n equity investments as of March 31, 2017

– Net unrealized appreciation on LMM equity investments of $161 million as of March 31, 2017 LMM Investment Portfolio is a pool of high quality, seasoned assets with attractive risk-adjusted return characteristics

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 8

LMM Portfolio by Industry (as a Percentage of Cost)

Energy Equipment & Services, 14% Machinery, 9% Construction & Engineering, 8% Hotels, Restaurants & Leisure, 7% Specialty Retail, 5% Computers & Peripherals, 5% Electronic Equipment, Instruments & Components, 5% Diversified Telecommunication Services, 4% Internet Software & Services, 4% Building Products, 4% Leisure Equipment & Products, 4% Diversified Consumer Services, 4% Health Care Equipment & Supplies, 3% Diversified Financial Services, 3% Commercial Services & Supplies, 3% Software, 3% IT Services, 2% Professional Services, 2% Health Care Providers & Services, 2% Consumer Finance, 2% Oil, Gas & Consumable Fuels, 1% Air Freight & Logistics, 1% Chemicals, 1% Paper & Forest Products, 1% Other, 3%

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 9

Acquisition LBO/MBO Growth Capital Recapitalization/ Refinancing

Diversified LMM Portfolio (as a Percentage of Cost)

Invested Capital by Geography(1)

18% 23% 40% 12% 7%

Invested Capital by Transaction Type

3% 38% 37% 22%

(1) Based upon portfolio company headquarters

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 10

A Mature and Diversified Portfolio – LMM Investments Greater than Five Years Old

Annual ROE

(1) Aging as of June 8, 2017; fair value as of March 31, 2017

($ in 000's) Remaining Initial Equity Investment Type Investment Date Ownership % In MAIN portfolio for > 10 years (1) 1 Houston Plating and Coatings, LLC Equity Only Jan-03 < 25% 4,230 2 Café Brazil, LLC Equity Only Apr-04 > 50% 5,900 3 KBK Industries, LLC Debt and Equity Jan-06 < 25% 9,847 4 Hawthorne Customs and Dispatch Services, LLC Equity Only Jan-06 25% to 50% 2,320 5 East Teak Fine Hardwoods, Inc. Equity Only Apr-06 < 25% 750 6 CBT Nuggets, LLC Equity Only Jun-06 25% to 50% 60,620 7 Jensen Jewelers of Idaho, LLC Debt and Equity Nov-06 > 50% 8,365 8 Mid-Columbia Lumber Products, LLC Debt and Equity Dec-06 > 50% 9,675 9 Vision Interests, Inc. Debt and Equity Jun-07 > 50% 5,814 Total - In MAIN portfolio for > 10 years 107,521 % of total LMM portfolio at fair value 12% In MAIN portfolio for > 8 years (1) 10 Gulf Manufacturing, LLC Debt and Equity Aug-07 25% to 50% 9,967 11 The MPI Group, LLC Debt and Equity Oct-07 > 50% 5,312 12 Hydratec, Inc. Equity Only Nov-07 > 50% 15,640 13 Uvalco Supply, LLC Debt and Equity Jan-08 > 50% 5,063 14 NAPCO Precast, LLC Debt and Equity Feb-08 25% to 50% 17,585 15 OMi Holdings, Inc. Equity Only Apr-08 25% to 50% 13,080 16 Lamb Ventures, LLC Debt and Equity May-08 > 50% 15,862 17 Condit Exhibits, LLC Equity Only Jul-08 < 25% 1,840 18 Ziegler’s NYPD, LLC Debt and Equity Oct-08 > 50% 8,384 Total - In MAIN portfolio for > 8 years 200,254 % of total LMM portfolio at fair value 23% Fair Value

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 11

A Mature and Diversified Portfolio – LMM Investments Greater than Five Years Old (continued)

Annual ROE

(1) Aging as of June 8, 2017; fair value as of March 31, 2017 (2) Since MAIN’s initial investment in this portfolio company, the portfolio company has completed one or more transactions whereby it sold or recapitalized a majority of its equity, and through these transactions MAIN retained a portion of its equity ownership in the portfolio company. The investment date listed here represents MAIN’s initial investment date in each portfolio company

($ in 000's) Remaining Initial Equity Investment Type Investment Date Ownership % In MAIN portfolio for > 6 years (1) 19 Indianapolis Aviation Partners, LLC Debt and Equity Sep-09 25% to 50% 5,810 20 Compact Power Equipment Centers Inc. Debt and Equity Sep-09 < 25% 8,680 21 Drilling Info Holdings, Inc.(2) Equity Only Nov-09 < 25% 10,100 22 Harrison Hydra-Gen, Ltd. Equity Only Jun-10 25% to 50% 2,800 23 PPL RVs, Inc. Debt and Equity Jun-10 > 50% 29,614 24 OPI International Ltd. Debt and Equity Nov-10 < 25% 853 25 irth Solutions, LLC(2) Equity Only Dec-10 < 25% 1,920 26 Pegasus Research Group, LLC Equity Only Jan-11 25% to 50% 8,440 27 Principle Environmental, LLC Debt and Equity Feb-11 > 50% 14,034 28 River Aggregates, LLC Debt and Equity Mar-11 25% to 50% 7,756 29 OnAsset Intelligence, Inc. Debt and Equity Apr-11 < 25% 4,654 Total - In MAIN portfolio for > 6 years 294,915 % of total LMM portfolio at fair value 33% In MAIN portfolio for > 5 years (1) 30 NRI Clinical Research, LLC Debt and Equity Sep-11 25% to 50% 7,803 31 SAFETY Investment Holdings, LLC(2) Equity Only Nov-11 < 25% 2,000 32 Gault Financial, LLC (RMB Capital, LLC) Debt and Equity Nov-11 < 25% 11,950 33 NRP Jones, LLC Debt and Equity Dec-11 > 50% 14,594 34 Ameritech College Operations, LLC Debt and Equity Mar-12 25% to 50% 6,839 35 Bridge Capital Solutions Corporation Debt and Equity Apr-12 25% to 50% 11,043 Total - In MAIN portfolio for > 5 years 349,144 % of total LMM portfolio at fair value 39% Fair Value

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 12

Portfolio Investments – Vintage Analysis ($ Invested)(1)

Annual ROE

(1) As of March 31, 2017 (2) Including Other Portfolio investments and excluding MAIN’s external investment manager, MSC Advisor I, LLC $- $50.0 $100.0 $150.0 $200.0 $250.0 $300.0 $350.0 $400.0 2011 and prior 2012 2013 2014 2015 2016 2017

($) in millions Lower Middle Market

Cost Fair Value $- $50.0 $100.0 $150.0 $200.0 $250.0 $300.0 $350.0 $400.0 2011 and prior 2012 2013 2014 2015 2016 2017

($) in millions Middle Market

Cost Fair Value $- $50.0 $100.0 $150.0 $200.0 $250.0 $300.0 $350.0 $400.0 2011 and prior 2012 2013 2014 2015 2016 2017

($) in millions Private Loan

Cost Fair Value $- $50.0 $100.0 $150.0 $200.0 $250.0 $300.0 $350.0 $400.0 2011 and prior 2012 2013 2014 2015 2016 2017

($) in millions Total(2)

Cost Fair Value

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 13

Portfolio Investments – Vintage Analysis (% Invested)(1)

(1) As of March 31, 2017 (2) Including Other Portfolio investments and excluding MAIN’s external investment manager, MSC Advisor I, LLC 0% 5% 10% 15% 20% 25% 30% 35% 40% 2011 and prior 2012 2013 2014 2015 2016 2017

% of total Lower Middle Market

Cost Fair Value 0% 5% 10% 15% 20% 25% 30% 35% 2011 and prior 2012 2013 2014 2015 2016 2017

% of total Middle Market

Cost Fair Value 0% 5% 10% 15% 20% 25% 30% 35% 2011 and prior 2012 2013 2014 2015 2016 2017

% of total Private Loan

Cost Fair Value 0% 5% 10% 15% 20% 25% 2011 and prior 2012 2013 2014 2015 2016 2017

% of total Total(2)

Cost Fair Value

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 14

Middle Market Liquidity Analysis(1)

(1) As of March 31, 2017; amounts and percentages are based upon the par value of debt investments (2) Expected Maturity represents MAIN’s estimated or anticipated repayment date based on historical trends in both MAIN’s portfolio and in the broader Middle Market $- $20.0 $40.0 $60.0 $80.0 $100.0 $120.0 $140.0 $160.0 2017 2018 2019 2020 2021 2022 2023 2024

($) in millions Contractual Maturity

Principal 0% 5% 10% 15% 20% 25% 30% 2017 2018 2019 2020 2021 2022 2023 2024

% of total Contractual Maturity

Principal $- $20.0 $40.0 $60.0 $80.0 $100.0 $120.0 $140.0 $160.0 $180.0 2017 2018 2019 2020 2021 2022 2023 2024

($) in millions Expected Maturity(2)

Principal 0% 5% 10% 15% 20% 25% 30% 2017 2018 2019 2020 2021 2022 2023 2024

% of total Expected Maturity(2)

Principal

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 15

Asset Management Business

In May 2012, MAIN(1) entered into an investment sub-advisory agreement with the investment advisor to HMS Income Fund, Inc. (HMS), a non-listed BDC

• MAIN(1) provides asset management services, including sourcing,

diligence and post-investment monitoring

• HMS has total assets of $1.0 billion as of March 31, 2017
• MAIN(1) receives 50% of the investment advisor’s base asset

management fee and incentive fees

– MAIN(1) base asset management fee – 1% of total assets – MAIN(1) incentive fees – 10% of net investment income above a hurdle and 10% of net realized capital gains

Benefits to MAIN

• No significant increases to MAIN’s operating costs to provide

services (utilize existing infrastructure and leverage fixed costs)

• No invested capital – monetizing the value of MAIN franchise
• Impact on MAIN’s financial results

– $2.2 million contribution to net investment income in the first quarter of 2017(2) – $7.9 million contribution to net investment income for the year ended December 31, 2016(2) – $33.5 million of cumulative unrealized appreciation as of March 31, 2017

MAIN’s asset management business represents additional income diversification and the opportunity for greater shareholder returns MAIN’s internally managed operating structure provides MAIN’s shareholders the benefits of this asset management business

(1) Through MAIN’s wholly owned unconsolidated subsidiary, MSC Advisor I, LLC (2) Contribution to Net Investment Income includes (a) dividend income received by MAIN from MSC Advisor I, LLC and (b) operating expenses allocated from MAIN to MSC Advisor I, LLC

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 16

Management Alignment

– Has asset growth been accretive to shareholders – earnings, dividend, NAV per share? – Benefits of internally managed structure

• Greater incentives to maximize increases to shareholder value and rationalize equity and debt capital raises
• No conflicts of interests; 100% of MAIN’s management efforts and activities are for the benefit of the BDC

– Favorable comparison of the above vs our peers, the vast majority of which have only increased assets under management, but not key shareholder value metrics

Management Ownership

– MAIN’s senior executives and Board of Directors own 3.2 million shares worth ~$121 million(3)

• $24.0 million purchased as part of or since 2007 IPO, including $3.8 million purchased in 2016 and Q1 2017

– Broad / significant ownership throughout greater MAIN team through restricted stock

• Focuses our personnel on key drivers of value to MAIN shareholders – DNII and NAV per share
• Restricted stock grants were greater than 40% of 2016 total compensation for executive management

Alignment of Interests Between MAIN Management and MAIN Investors

MAIN Growth % Total Assets Total Assets Per Share DNII Per Share(1) Dividends Per Share(2) NAV Per Share 1-YR

11% 3% 3% 4% 4%

3-YR

53% 12% 10% 17% 11%

5-YR

182% 39% 35% 39% 45%

From End of IPO Year

1089% 96% 214% 65% 72%

(1) Distributable net investment income (DNII) is net investment income excluding the impact of share-based compensation expense which is non-cash in nature (2) Excludes supplemental/special dividends (3) Based upon closing market price of $38.27/share on March 31, 2017

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 17

MAIN Maintains a Significant Operating Cost Advantage

Efficient and leverageable

• perating structure

MAIN’s internally managed operating structure provides significant operating leverage and greater returns for our shareholders

(1) Total operating expenses, including non-cash share based compensation expense and excluding interest expense (2) For the trailing twelve month period ended March 31, 2017 (3) Other BDCs includes dividend paying BDCs that have been publicly-traded for at least two years and have total assets greater than $500 million based on individual SEC Filings as of December 31, 2016; specifically includes: AINV, ARCC, BKCC, CPTA, FDUS, FSC, FSFR, FSIC, GBDC, HTGC, MCC, MFIN, NMFC, PFLT, PNNT, PSEC, SLRC, SUNS, TCAP, TCPC, TCRD, TICC and TSLX (4) Calculation represents the average for the companies included in the group and is based upon the trailing twelve month period ended December 31, 2016 as derived from each company’s SEC filings (5) Source: SNL Financial. Calculation represents the average for the trailing twelve month period ended December 31, 2016 and includes commercial banks with a market capitalization between $125 million and $2 billion

0.0% 0.5% 1.0% 1.5% 2.0% 2.5% 3.0% 3.5% 4.0%

MAIN (2) Other BDCs (3)(4) Commercial Banks (5)

Operating Expenses as a Percentage of Total Assets(1)

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 18

MAIN Maintains a Significant Operating Cost Advantage

BDC Manager Costs Relative to Total Economic Profit Generated (dollars in thousands)

Annual ROE

(1) Source: Public company filings (2) Amounts represent the most recent five prior fiscal years ended for each respective company. For each applicable BDC not > 5 years past IPO, the first full fiscal year-end post-IPO was used as the starting point for this analysis as follows: CPTA – 2014; FSFR – 2014; FSIC – 2015; TCPC – 2013 and TSLX – 2015. NMFC amounts represent the most recent three prior fiscal years since management fees were not presented for FY 2012 and FY 2013 in NMFC’s SEC filings (3) Includes all BDCs with total assets greater than $500 million as of December 31, 2016, with the exception of MFIN which is excluded due to the non-traditional nature of their business plan and operations compared to most BDCs

Dividend Paying BDCs Public for > 2 Years(3) Management Structure Net Increase in Net Assets (Net Income) Add back: Compensation and Mgmt Fees Gross Economic Profit Before Management Costs % Economic Profits Paid to Management MAIN Internal 545,329 $ 81,720 $ 627,049 $ 13.0% Apollo Investment Corporation External 319,975 493,546 813,521 60.7% Ares Capital Corporation External 2,513,000 1,200,033 3,713,033 32.3% BlackRock Capital Investment Corporation External 241,913 191,871 433,784 44.2% Capitala Finance Corp. External 19,562 43,221 62,783 68.8% Fidus Investment Corporation External 133,646 64,534 198,180 32.6% Fifth Street Finance Corp. External 242,593 336,785 579,378 58.1% Fifth Street Senior Floating Rate Corp. External 20,818 25,278 46,096 54.8% FS Investment Corporation External 332,676 238,472 571,148 41.8% Golub Capital BDC, Inc. External 283,663 123,339 407,002 30.3% Hercules Capital, Inc. Internal 329,012 125,497 454,509 27.6% Medley Capital Corporation External 71,260 138,193 209,453 66.0% New Mountain Finance Corporation External 190,208 100,534 290,742 34.6% PennantPark Floating Rate Capital Ltd. External 90,453 27,809 118,262 23.5% PennantPark Investment Corporation External 274,605 193,530 468,135 41.3% Prospect Capital Corporation External 1,180,481 933,998 2,114,479 44.2% Solar Capital Ltd. External 360,418 197,466 557,884 35.4% Solar Senior Capital Ltd. External 63,519 14,973 78,492 19.1% TCP Capital Corp. External 219,460 59,942 279,402 21.5% THL Credit, Inc. External 152,452 91,667 244,119 37.6% TICC Capital Corp. External 168,148 109,173 277,321 39.4% TPG Specialty Lending, Inc. External 200,575 87,756 288,331 30.4% Triangle Capital Corporation Internal 251,751 89,388 341,139 26.2% Peer Group Average 39.6% 5 Year Total(1)(2)

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 19

Historical Dividend, DNII and NAV Per Share Growth

MAIN’s unique focus

• n equity investments

in the Lower Middle Market provides the

• pportunity for

significant NAV per share growth MAIN’s efficient

• perating structure

provides significant

• perating leverage,

greater dividends and greater overall returns for our shareholders MAIN’s dividends have been covered by DNII and net realized gains – MAIN has never paid a return of capital distribution

• Includes recurring monthly and supplemental dividends paid and declared

as of June 7, 2017.

• Annual return on equity averaging approximately 13.8% from 2010 through

the first quarter of 2017

MAIN (2) Internally Managed BDC’s (3)(5) Externally Managed BDC’s (4)(5)

$8.00 $10.00 $12.00 $14.00 $16.00 $18.00 $20.00 $22.00 $24.00 $0.20 $0.30 $0.40 $0.50 $0.60 $0.70 $0.80 $0.90

Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017

NAV Per Share DNII and Dividends Per Share Regular Dividends Supplemental Dividends DNII per share NAV per share $0.00

Recessionary Period

2007 207 2007

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 20

MAIN Strategy Produces Differentiated Returns

Historical Monthly Dividend Growth and Coverage of Monthly Dividends with Earnings(1)

(1) Sources: Yearly dividends per share from individual company website; does not include supplemental dividends (2) Includes all BDCs with total assets greater than $500 million as of December 31, 2016, with the exception of MFIN, which is excluded due to the non-traditional nature of their business plan and operations compared to most BDCs

Dividends Per Share

2011 2012 2013 2014 2015 2016 MAIN $1.56 $1.71 $1.86 $2.00 $2.10 $2.18 6.87% 5.35% 102.3% Apollo Investment Corporation $1.12 $1.04 $0.80 $0.80 $0.80 $0.75

• 7.71%
• 2.13%

93.2% Ares Capital Corporation $1.41 $1.50 $1.52 $1.52 $1.52 $1.52 1.51% 0.00% 103.5% BlackRock Capital Investment Corporation $1.10 $1.04 $1.04 $0.94 $0.84 $0.84

• 5.25%
• 6.87%

88.4% Fidus Investment Corporation N/A $1.46 $1.52 $1.52 $1.54 $1.56 NM 0.87% 93.3% Fifth Street Finance Corporation $1.28 $1.18 $1.15 $1.03 $0.69 $0.72

• 10.87%
• 14.45%

98.7% Golub Capital BDC, Inc. $1.28 $1.28 $1.28 $1.28 $1.28 $1.28 0.00% 0.00% 98.9% Hercules Capital, Inc. $0.88 $0.95 $1.11 $1.24 $1.24 $1.24 7.10% 3.76% 109.7% Medley Capital Corporation N/A $1.31 $1.46 $1.48 $1.20 $1.04 NM

• 10.69%

84.1% New Mountain Finance Corporation N/A $1.34 $1.36 $1.36 $1.36 $1.36 NM 0.00% 88.9% PennantPark Floating Rate Capital Ltd. N/A $0.94 $1.04 $1.08 $1.13 $1.14 NM 3.11% 95.4% Pennant Park Investment Corp. $1.07 $1.12 $1.12 $1.12 $1.12 $1.12 0.92% 0.00% 86.3% Prospect Capital Corporation $1.21 $1.22 $1.28 $1.33 $1.05 $1.00

• 3.75%
• 7.91%

95.9% Solar Capital Ltd. $2.40 $1.80 $2.20 $1.60 $1.60 $1.60

• 7.79%
• 10.07%

105.2% Solar Senior Capital Ltd. N/A $1.16 $1.41 $1.41 $1.41 $1.41 NM 0.00% 100.9% THL Credit, Inc. $1.17 $1.29 $1.43 $1.36 $1.36 $1.29 1.97%

• 3.38%

104.4% TICC Capital Corp. $0.99 $1.12 $1.16 $1.16 $1.14 $1.16 3.22% 0.00% 39.9% Triangle Capital Corporation $1.77 $2.02 $2.16 $2.16 $2.16 $1.89 1.32%

• 4.35%

85.6% Peer Group Average

• 1.61%
• 3.07%

92.5% Dividend Paying BDCs Public for > 5 Years(2) Coverage? 2016 NII /

• Mo. Dividend

5-YR CAGR 3-YR CAGR Monthly Dividends Per Share

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 21

MAIN Strategy Produces Differentiated Returns

Dividend Yield Does Not Equal Economic Shareholder Return and Can Be Very Misleading Return of Capital Distributions Do Not Equal Investment Return to Shareholders

(1) Includes all BDCs with total assets greater than $500 million as of December 31, 2016, with the exception of MFIN, which is excluded due to the non-traditional nature of their business plan and operations compared to most BDCs (2) Realized Income = Net Investment Income plus Net Realized Gains / (Losses) on investments (3) Includes Total Distributions Paid to shareholders (4) Calculation is (a) (i) Total Distributions Paid divided by (ii) Beginning Market Price Per Share divided by (b) number of years included in analysis (based upon each company's respective IPO date). For each applicable BDC not > 6 years past IPO, the first full 12/31 calendar year-end post-IPO is as follows: CPTA – 2014; FDUS – 2012; FSFR – 2014; FSIC – 2015; MCC – 2012; NMFC – 2012; PFLT – 2012; SUNS – 2012; TCPC – 2013 and TSLX – 2015. (5) Realized Income Per Share minus Total Distributions Paid Per Share (6) Adjusted Profit Distributions = Total Distributions Paid Per Share plus Net Excess Earnings / (Return of Capital); % result is based upon the same calculation as footnote (4) above

Avg Dist Paid Net Excess Avg Adj'd Per Yr as a Earnings / Profit Dist Per Dividend Paying BDCs % of Beg Mkt (Return of Yr as % of Beg Public for > 2 Years(1) Cumulative Cumulative Price (4) Capital) (5) Mkt Price (6) MAIN 13.93 13.85 12.7% 0.08 12.8% Apollo Investment Corporation 1.17 5.31 8.0% (4.14) 1.8% Ares Capital Corporation 11.11 9.24 9.3% 1.87 11.2% BlackRock Capital Investment Corporation 4.09 5.80 8.7% (1.71) 6.2% Capitala Finance Corp. 4.02 5.76 9.6% (1.74) 6.7% Fidus Investment Corporation 9.00 8.32 12.8% 0.68 13.9% Fifth Street Finance Corp. 3.14 6.05 8.3% (2.91) 4.3% Fifth Street Senior Floating Rate Corp. 3.15 3.20 8.1% (0.05) 7.9% FS Investment Corporation 1.43 1.63 8.2% (0.21) 7.2% Golub Capital BDC, Inc. 7.62 7.93 7.7% (0.31) 7.4% Hercules Capital, Inc. 7.56 6.66 10.7% 0.90 12.2% Medley Capital Corporation 4.69 6.49 12.5% (1.80) 9.0% New Mountain Finance Corporation 6.38 7.39 11.0% (1.01) 9.5% PennantPark Floating Rate Capital Ltd. 5.99 5.32 10.3% 0.67 11.6% PennantPark Investment Corp. 6.15 6.67 9.1% (0.52) 8.4% Prospect Capital Corporation 6.65 7.09 10.9% (0.43) 10.3% Solar Capital Ltd. 8.21 11.20 7.5% (2.99) 5.5% Solar Senior Capital Ltd. 6.02 6.80 6.2% (0.78) 5.5% TCP Capital Corp. 4.96 5.95 10.1% (0.99) 8.4% THL Credit, Inc. 6.58 7.95 10.2% (1.37) 8.4% TICC Capital Corp. 5.19 6.73 10.0% (1.54) 7.7% TPG Specialty Lending, Inc. 3.54 3.12 9.3% 0.42 10.5% Triangle Capital Corporation 13.48 12.76 11.2% 0.72 11.8% Peer Group Average 9.5% 8.4% Realized Income Per Share 2011 - 2016(2) Total Distributions Paid Per Share 2011 - 2016 (3)

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 22

MAIN Strategy Produces Differentiated Returns

Total Shareholder Returns are Better Indicator of Economic Value Creation for Shareholders

(1) Includes all BDCs with total assets greater than $500 million as of December 31, 2016, with the exception of MFIN, which is excluded due to the non-traditional nature of their business plan and operations compared to most BDCs (2) Represents either (a) 12/31/10 if BDC has been public > 6 years or (b) the first 12/31 date after IPO date. For each applicable BDC not > 6 years past IPO, the beginning 12/31 period is as follows: CPTA – 12/31/13; FDUS – 12/31/11; FSFR – 12/31/13; FSIC – 12/31/14; MCC – 12/31/11; NMFC – 12/31/11; PFLT – 12/31/11; SUNS – 12/31/11; TCPC – 12/31/12 and TSLX 12/31/14 (3) Represents either (a) dividends for full 6 years if BDC has been public > 6 years or (b) dividends from first full 12/31 calendar year-end after IPO date through 12/31/16. See footnote (4) on page 21 for details (4) Calculation is (a) (i) Total NAV Change Plus Distributions Paid per Share divided by (ii) Beginning NAV divided by (b) number of years included in analysis (based upon IPO date) (5) Calculation is (a) (i) Total Market Price Change Plus Distributions Paid per Share divided by (ii) Beginning Market Price divided by (b) number of years included in analysis (based upon IPO date)

Increase Distributions NAV Change Avg Ann'l Increase Distributions Mkt Price Chg Avg Ann'l Dividend Paying BDCs Public (Decrease) in Paid Per Share Plus Distrib Return as a % (Decrease) in Paid Per Share Plus Distrib Return as a % for > 2 Years (1) Beg (2) 12/31/16 NAV Per Share 2011-2016 (3) Per Share

• f Beg NAV (4)

Beg (2) 12/31/16 Market Price 2011-2016 (3) Per Share Beg Mkt Price (5) MAIN 13.06 22.10 9.04 13.85 22.89 29.2% 18.19 36.77 18.58 13.85 32.43 29.7% Apollo Investment Corporation 9.73 6.86 (2.87) 5.31 2.44 4.2% 11.07 5.86 (5.21) 5.31 0.10 0.2% Ares Capital Corporation 14.92 16.45 1.53 9.24 10.77 12.0% 16.48 16.49 0.01 9.24 9.25 9.4% BlackRock Capital Investment Corporation 9.62 8.21 (1.41) 5.80 4.39 7.6% 11.06 6.96 (4.10) 5.80 1.70 2.6% Capitala Finance Corp. 20.71 15.79 (4.92) 5.76 0.84 1.4% 19.90 12.93 (6.97) 5.76 (1.21)

• 2.0%

Fidus Investment Corporation 14.90 15.76 0.86 8.32 9.18 12.3% 12.97 15.73 2.76 8.32 11.08 17.1% Fifth Street Finance Corp. 10.44 7.31 (3.13) 6.05 2.92 4.7% 12.14 5.37 (6.77) 6.05 (0.72)

• 1.0%

Fifth Street Senior Floating Rate Corp. 15.10 10.86 (4.24) 3.20 (1.04)

• 2.3%

13.24 8.71 (4.53) 3.20 (1.33)

• 3.3%

FS Investment Corporation 9.83 9.41 (0.42) 1.63 1.21 6.2% 9.93 10.30 0.37 1.63 2.00 10.1% Golub Capital BDC, Inc. 14.74 15.74 1.00 7.93 8.93 10.1% 17.12 18.39 1.27 7.93 9.20 9.0% Hercules Capital, Inc. 9.50 9.90 0.40 6.66 7.06 12.4% 10.36 14.11 3.75 6.66 10.41 16.7% Medley Capital Corporation 12.57 9.39 (3.18) 6.49 3.31 5.3% 10.40 7.51 (2.89) 6.49 3.60 6.9% New Mountain Finance Corporation 13.60 13.46 (0.14) 7.39 7.25 10.7% 13.41 14.10 0.69 7.39 8.08 12.1% PennantPark Floating Rate Capital Ltd. 13.68 14.11 0.43 5.32 5.75 8.4% 10.30 14.11 3.81 5.32 9.13 17.7% PennantPark Investment Corp. 11.14 9.11 (2.03) 6.67 4.64 6.9% 12.25 7.66 (4.59) 6.67 2.08 2.8% Prospect Capital Corporation 10.25 9.62 (0.63) 7.09 6.46 10.5% 10.80 8.35 (2.45) 7.09 4.64 7.2% Solar Capital Ltd. 22.73 21.74 (0.99) 11.20 10.21 7.5% 24.78 20.82 (3.96) 11.20 7.24 4.9% Solar Senior Capital Ltd. 18.15 16.80 (1.35) 6.80 5.45 6.0% 22.09 16.44 (5.65) 6.80 1.15 1.0% TCP Capital Corp. 14.71 14.91 0.20 5.95 6.15 10.5% 14.74 16.90 2.16 5.95 8.11 13.8% THL Credit, Inc. 13.06 11.82 (1.24) 7.95 6.71 8.6% 13.01 10.01 (3.00) 7.95 4.95 6.3% TICC Capital Corp. 9.85 7.50 (2.35) 6.73 4.38 7.4% 11.21 6.61 (4.60) 6.73 2.13 3.2% TPG Specialty Lending, Inc. 15.53 15.95 0.42 3.12 3.54 11.4% 16.82 18.68 1.86 3.12 4.98 14.8% Triangle Capital Corporation 12.09 15.13 3.04 12.76 15.80 21.8% 19.00 18.34 (0.66) 12.76 12.10 10.6% Peer Group Average 8.3% 7.3% Net Asset Total Shareholder Return - Economic Value Total Shareholder Return - Market Value Closing Trading Price Per Share Value Per Share

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 23

MAIN Strategy Produces Differentiated Returns

Preserving (or Increasing) Value through Economic Cycles? Declining NAV = Risk to Investors

Note: MAIN NAV/Share growth primarily generated through retained earnings(3) (~25%) and accretive offerings (~75%) Source: Individual company filings

(1) Includes all BDCs with total assets greater than $500 million as of December 31, 2016, with the exception of MFIN, which is excluded due to the non-traditional nature of their business plan and operations compared to most BDCs (2) As of December 31, 2016 (3) Retained earnings includes cumulative net investment income, net realized gains and net unrealized appreciation, net of cumulative dividends paid or accrued

NAV/Share

12/31/2011 12/31/2016 % Growth (Decline) MAIN $15.19 $22.10 45.5% 7.8% 3.6% 105% Apollo Investment Corporation $8.16 $6.86

• 15.9%
• 3.4%
• 7.2%

50% Ares Capital Corporation $15.34 $16.45 7.2% 1.4% 0.0% 98% BlackRock Capital Investment Corporation $9.58 $8.21

• 14.3%
• 3.0%
• 4.9%

68% Fidus Investment Corporation $14.90 $15.76 5.8% 1.1% 0.9% 104% Fifth Street Finance Corporation $9.89 $7.31

• 26.1%
• 5.9%
• 9.5%

65% Golub Capital BDC, Inc. $14.53 $15.74 8.3% 1.6% 1.1% 101% Hercules Capital, Inc. $9.83 $9.90 0.7% 0.1%

• 2.0%

94% Medley Capital Corporation $12.57 $9.39

• 25.3%
• 5.7%
• 9.5%

72% New Mountain Finance Corporation $13.60 $13.46

• 1.0%
• 0.2%
• 2.2%

94% PennantPark Floating Rate Capital Ltd. $13.68 $14.11 3.1% 0.6%

• 0.3%

102% PennantPark Investment Corp. $10.19 $9.11

• 10.6%
• 2.2%
• 5.5%

79% Prospect Capital Corporation $10.69 $9.62

• 10.0%
• 2.1%
• 3.6%

87% Solar Capital Ltd. $22.02 $21.74

• 1.3%
• 0.3%
• 1.1%

93% Solar Senior Capital Ltd. $18.15 $16.80

• 7.4%
• 1.5%
• 2.3%

94% THL Credit, Inc. $13.24 $11.82

• 10.7%
• 2.2%
• 4.0%

89% TICC Capital Corp. $9.30 $7.50

• 19.4%
• 4.2%
• 8.7%

69% Triangle Capital Corporation $14.68 $15.13 3.1% 0.6%

• 2.1%

89% Peer Group Average

• 6.7%
• 1.5%
• 3.6%

85% Dividend Paying BDCs Public for > 5 years(1) 3-YR CAGR 5-YR CAGR Current NAV/ Cumulative Equity Capital Raised(2) NAV / Share

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 24

MAIN Strategy Produces Differentiated Returns

Operating Efficiency and Superior Underwriting Produces Superior Returns

(1) ROE calculated as Net Increase in Net Assets divided by average Net Asset Value for each respective measurement period through December 31, 2016 (2) Includes all BDCs with total assets greater than $500 million as of December 31, 2016, with the exception of MFIN, which is excluded due to the non-traditional nature of their business plan and operations compared to most BDCs. (3) MAIN Net Increase in Net Assets in ROE calculation excludes impact from changes in fair value (unrealized or realized) relating to SBIC debentures

Annual ROE

7-YR 5-YR 3-YR MAIN (3) 14.1% 13.3% 11.7% Apollo Investment Corporation 4.0% 6.0% 2.0% Ares Capital Corporation 12.1% 10.5% 9.3% BlackRock Capital Investment Corporation 8.0% 6.8% 4.2% Capitala Finance Corp. N/A N/A 2.5% Fidus Investment Corporation N/A 11.8% 11.4% Fifth Street Finance Corp. 2.9% 2.7%

• 1.2%

Fifth Street Senior Floating Rate Corp. N/A N/A 2.3% FS Investment Corporation N/A N/A N/A Golub Capital BDC, Inc. N/A 9.1% 9.0% Hercules Capital, Inc. 9.5% 10.3% 8.6% Medley Capital Corporation N/A 3.0% 0.1% New Mountain Finance Corporation N/A 8.1% 7.9% PennantPark Floating Rate Capital Ltd. N/A 8.6% 8.1% PennantPark Investment Corp. 7.5% 8.3% 4.9% Prospect Capital Corporation 9.1% 8.5% 7.4% Solar Capital Ltd. N/A 7.8% 6.1% Solar Senior Capital Ltd. N/A 6.3% 5.8% TCP Capital Corporation N/A N/A 8.2% THL Credit, Inc. N/A 7.7% 6.4% TICC Capital Corp. 8.7% 7.5% 2.9% TPG Specialty Lending, Inc. N/A N/A N/A Triangle Capital Corporation 11.9% 10.6% 7.1% Peer Group Average 8.2% 7.8% 5.7% Dividend Paying BDCs Public for > 2 Years(2) Annual Return on Equity (ROE)(1)

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 25

Perspective on Total Return Since IPO

• 20% -14%
• 8%
• 2%

4% 10% 16% 22% OHAI MFIN KCAP MVC AINV BKCC PSEC SAR PNNT TICC GAIN CSWC HTGC ARCC NEWT TCAP MAIN

• 100%

25% 150% 275% 400% 525% OHAI MFIN KCAP MVC AINV BKCC PSEC SAR PNNT TICC GAIN CSWC HTGC ARCC NEWT TCAP MAIN Annual Total Return (%)* Total Return (%)*

*Note: Bloomberg data from BDCs in existence since October 5, 2007 and assuming dividends were reinvested in each security; return analysis is through June 1, 2017

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 26

# Company Total Return # Company Total Return 1 NETFLIX INC 5086.0% 14 APPLE INC 634.7% 2 REGENERON PHARMACEUTICALS 2490.4% 15 REYNOLDS AMERICAN INC 632.8% 3 PRICELINE GROUP INC/THE 1913.0% 16 O'REILLY AUTOMOTIVE INC 632.4% 4 INCYTE CORP 1610.1% 17 ALLERGAN PLC 616.4% 5 ALASKA AIR GROUP INC 1341.6% 18 CENTENE CORP 588.8% 6 SKYWORKS SOLUTIONS INC 1128.2% 19 SALESFORCE.COM INC 576.7% 7 TRANSDIGM GROUP INC 987.0% 20 EXTRA SPACE STORAGE INC 568.5% 8 AMAZON.COM INC 966.0% 21 ILLUMINA INC 533.2% 9 ROSS STORES INC 923.3% 22 MAIN STREET CAPITAL CORP 520.7% 10 EDWARDS LIFESCIENCES CORP 811.3% 23 SHERWIN-WILLIAMS CO/THE 499.1% 11 MASTERCARD INC - A 693.1% 24 IDEXX LABORATORIES INC 498.8% 12 CONSTELLATION BRANDS INC-A 655.8% 25 TJX COMPANIES INC 491.7% 13 CONCHO RESOURCES INC 641.3%

Amongst current S&P 500 constituents in existence since October 5, 2007, MAIN’s Total Return Since IPO ranks #22 – This result places MAIN’s total return performance in the top 5% of this comparable group

Perspective on Total Return Since IPO

*Note: Bloomberg data from all current constituents of the S&P 500 in existence since October 5, 2007 and assuming dividends were reinvested in each security; return analysis is through June 1, 2017

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 27 Notes: (1) Assumes dividends reinvested on date paid (2) The Main Street Peer Group includes all BDCs that have been publicly-traded for at least one year and that have total assets greater than $500 million based on individual SEC Filings as of December 31, 2016; specifically includes: AINV, ARCC, BKCC, CPTA, FDUS, FSC, FSFR, FSIC, GBDC, GSBD, HTGC, MCC, MFIN, NMFC, PFLT, PNNT, PSEC, SLRC, SUNS, TCAP, TCPC, TCRD, TICC, and TSLX (3) Main Street Peer Group is equal weighted (4) Indexed as of October 5, 2007 and last trading date is March 31, 2017

Consistent market outperformance through various economic cycles

MAIN Total Return Performance Since IPO

Recessionary Period

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

MAIN (2)

Chad Green

President

Steven Geuther

Associate Main Street Capital Corporation

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Main Street’s View of Transaction and Background

Business: Casing and tubing coating for downhole corrosion prevention and cement adhesion Original Investment Date: December 2012 Investment Type:

• Minority equity investment
• First lien, senior secured

debt investment Transaction Type: Minority recapitalization to facilitate generational transfer Capital Invested: $21.4 million ($15.0 million debt and $6.4 million common equity) Proprietary product and machinery

• Well-regarded business with a proprietary product and strong record

as an industry leader

• Innovative and proprietary machinery, creating significant barriers to

entry and maximizing production efficiencies Favorable transaction rationale

• MAIN

provided entirety

• f

capital required to facilitate the transaction, resulting in the family retaining control of the business and Main Street’s ownership percentage of approximately 49%

• Allowed the first generation founder to achieve full liquidity and retire

while his son (Chad Green, President) rolled the majority of his proceeds, creating an alignment of incentives for all shareholders going forward without the family giving up control of the business Significant growth potential in domestic and international markets

• With a strong foothold in the Permian Basin and the addition of a

key sales manager, the Company has been able to rapidly acquire new customers domestically given the superiority of the product and lack of viable alternatives

• The Company has meaningful opportunity for growth via expansion

in the Middle East and other international markets given its existing joint venture in Oman and recently awarded joint venture in Qatar Opportunity to partner with strong existing owner / operator

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Company Overview

• Bond-Coat, Inc. (“Bond-Coat” or the “Company”) is an

industry leader in downhole, external casing and tubing coatings for corrosion prevention and cement adhesion in

• il and gas drilling & production.
• Headquartered in Midland, Texas, the Company began
• perations in 1964 with its original product, Ruff-Coat,

which was designed to achieve a better wellbore cement to casing bond as well as to provide a protective coating to tanks and other oil field equipment. – Ruff-Coat has since been essentially phased out, as Flint-Coat is the primary offering.

• Bond-Coat’s proprietary product used today, Flint-Coat, is

a mix of epoxy and flint aggregate which includes a layer

• f resin, a layer of flint and a second layer of resin which

is all applied after the pipe has been sandblasted using a proprietary process.

• While the majority of Bond-Coat’s domestic coated pipe is

utilized in the Permian Basin, the Company entered into a Joint Venture in Oman in 2010: – The Oman J.V. is owned 50% by Bond-Coat, and utilizes blasting and coating machinery built by Bond-Coat and the Flint-Coat proprietary mix.

Midland, TX Headquarters Finished Product: Coated Casing

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Product Overview: Flint-Coat

• Flint-Coat

is a proprietary and unique product that is applied externally to oil and gas production casing to prevent downhole external corrosion.

• Flint-Coat is differentiated from other similar

products in the market as it can achieve corrosion resistance, abrasion resistance and cement adhesion at the same time, which are unique selling points and provide Bond-Coat significant competitive advantages.

• Flint-Coat

is also the cheapest solution available in the market, compared to both direct and indirect competitors, as well as

• ther alternatives.

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Downhole Casing Corrosion Overview

• In the oil & gas industry, downhole external casing corrosion is an issue with which many operators have to

address on a day to day basis. – Numerous production casing failures due to external corrosion have been reported in regions such as West Texas, Middle East and North Africa.

• Cement failure caused by a poor cement job and ‘theft zones’ in the formation are the primary reasons

potentially leading to external casing corrosion. – Casing corrosion will result not only in the loss of the casing but also the interruption of production, loss of well, or even permanent damage to the reservoir.

• Nearly all causes of external casing corrosion (dissimilar metal corrosion, dissimilar soils, differential

aeration, bacteria, “stray current” interference) are highly likely when the casing is attacked by saline water, resulting from a cement failure.

• A significant portion of oil and gas fields worldwide are exposed to saline aquifers, especially in the US,

Middle East, Far East and North Africa. – The Middle East is one area that is most significantly covered by saline aquifers and external casing corrosion is one of the most common problems with well integrity in that region.

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Cement Adhesion Overview

• An added benefit to corrosion control is achieved when

using Flint-Coat through the production zone where cement is applied. – The illustration shows a common communication problem. – As oil enters the casing, some of the production can be lost to a thief zone via a micro annulus from an imperfect cement bond to untreated casing.

• Another costly problem is water encroachment into the

production zone. – With the cement adhering to the Flint-Coat, a near perfect bond is achieved. – Wellbore and casing become

• ne,

leaving no avenue for communication. No coating Flint-Coat

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Flint-Coat – Coating Process

1. Surface Preparation: – New and used casing and tubing go through Bond-Coat’s automated, proprietary grit blasting machine, removing any surface contaminants and creating a rough profile to increase adhesion. 2. Coating Application: – Once the joints have been blasted, each joint is then coated with Bond-Coat’s proprietary mix of epoxy resin followed by a layer of flint aggregate. – The Flint-Coat aggregate and epoxy resin then cures in a rolling oven and a final layer

• f resin is applied.

– The process

• f

placing flint aggregate between two layers of resin results in a reinforced coating which is tougher than any

• ther coating or wrap in the world.

3. Quality Control & Inspection

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Proprietary Machinery & Coating Line

• The Company’s proprietary sandblasting and coating machinery is custom-built and maintained in-house,

creating a scalable, significant barrier to entry: – Bond-Coat can sandblast and coat several times more feet per hour than any known competitor. – The Company’s blasting and coating lines are highly scalable, enabling them to be built at its headquarters in Midland and shipped to other areas to be assembled (i.e. the Oman J.V.).

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Representative Customers

• Bond-Coat’s domestic and international customers represent some of the largest major and

independent exploration & production companies in the industry.

• These customers have proven the effectiveness of Flint-Coat through extensive field and

laboratory testing.

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

International Growth – Recent Developments

• After extensive testing and trials, Bond-Coat recently

received a contract with Qatar Petroleum: – The Company is currently building additional equipment for a coating line to send to a new joint venture facility in Doha, Qatar. – Consistent with practices employed by other major, foreign oil & gas related businesses in Qatar, the Company will be forming a joint venture with Petroleum Technology Co. in Doha. – The contract is initially for $3.75 million over three years, but Bond-Coat believes the volume and additional work that will likely come from Qatar’s

• ffshore state drilling company could potentially result

in annual revenues greater than $5 million.

• Bond-Coat has been in discussions to coat pipe for Saudi

Aramco for several years, and has undergone extensive laboratory testing: – Bond-Coat was awarded the opportunity to participate in the final stage of required testing in Q1 2017, in which Saudi Aramco put Bond-Coat’s coated casing downhole and, after a period of 6-12 months, will run a logging tool downhole to measure or detect any corrosion. – Bond-Coat anticipates entering into a contract with Saudi Aramco by Q1 2018.

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

International Growth – Additional Opportunities

• The Company has received significant interest from Abu

Dhabi Company for Onshore Oil Operations (“ADCO”), the company responsible for over half of Abu Dhabi’s oil output, and Upper Zakum Offshore Oil Field Development,

• r

ZADCO, a joint venture with Exxon Mobil. – ADCO is in the process of issuing a purchase order to Bond-Coat for a test trial in 2017.

• The Company has also received significant interest in its

product from another major operator in Abu Dhabi: the Abu Dhabi Marine Operating Company (“ADMA”).

• ADMA has issued a purchase order for a test trial to be

conducted in the Oman facility.

• Chad Green, Bond-Coat’s majority owner and President, has

spent extensive time overseas this year for testing and additional meetings.

• Statoil Petroleum expressed strong interest in Flint-Coat for

drilling activities in the North Sea.

• Statoil conducted a recent test comparing Flint-Coat to

uncoated casing to determine the cement bonding capabilities, and had to quit mid-test as they could not remove the cement/coating from the pipe to even get a metallurgical reading, illustrating the extreme bonding capabilities of Flint-Coat.

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Historical Timeline and Valuations

A – Q4 2012 MAIN completes minority recap C – Q2,Q3 2014 WTI crude spot price: $107.95 per barrel; US Onshore Rig Count: 1,931 G – Q1 2017 Bond-Coat awarded field test for Saudi Aramco; coated casing currently downhole for removal & testing in 2H 2017 E – Q1,Q2 2016 WTI crude spot price falls to $26.19 per barrel; US Onshore Rig Count falls to 404 D – Q2 2015 Bond-Coat hires Sales Manager, Joe Thaggard

2012 2013 2014 2015 2016 2017

F – Q4 2016 Bond-Coat substantially completes its second automated coating line in Midland H – Q2 2017 Bond-Coat awarded contract with Qatar Petroleum, begins join venture formation B – Q1 2013 Bond-Coat hires Operations Manager, Tom Soule (A) (F) (B) (C) (D) (E) (G) (H)

$6.4 $6.2 $6.2 $6.4 $6.4 $6.4 $6.4 $6.4 $6.4 $6.4 $6.4 $6.4 $6.4 $6.4 $6.4 $6.4 $8.9 $9.3 $10.5 $11.2 $11.2 $10.2 $10.2 $10.2 $9.1 $7.5 $5.1 $5.1 $6.7 $7.6

• 100.0%

0.0% 100.0% 200.0% 300.0% 400.0% 500.0% $0 $2 $4 $6 $8 $10 $12 Dec-12 Dec-13 Mar-14 Jun-14 Sep-14 Dec-14 Mar-15 Jun-15 Sep-15 Dec-15 Mar-16 Jun-16 Sep-16 Dec-16 Mar-17 (Equity Cost and FV $ in millions) Equity Cost ($) Equity Fair Value ($) EBITDA Growth % From Original Investment Date Net Debt to EBITDA as a %

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

MAIN (2)

Colton Braud

Managing Director Main Street Capital Corporation

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

2 Page

Location Marietta, Georgia Business Provider of clinical respiratory and durable medical equipment for pediatric patients Website www.softtouchmedical.com Original Investment Date October 2014 Investment Type First lien, senior secured term loan Majority equity investment Transaction Type Majority recapitalization transitioning leadership of the Company to its current CEO and to support growth initiatives Capital Invested $15.9 million ($10.0 million debt and $5.9 million equity) – 85% MAIN / 15% HMS

Main Street’s View of Transaction and Background

1. Family-owned and operated business with market leading position in the Greater Atlanta Metropolitan area 2. Cash flow positive every year since inception in 1997 3. Historically undercapitalized business with the majority of free cash flow being paid as distributions to the Company founder 4. Recapitalization transaction with Main Street allowed all family members to obtain partial or full liquidity and firmly positioned Kathleen Yeakey as CEO 5. Talented, motivated executive ready for CEO ascension 6. Longstanding relationships with the primary pediatric referral sources in Atlanta and throughout the state of Georgia 7. High barriers to entry due to accreditation process and high standard of care required for pediatric patients 8. Recurring rental revenue drives sales of consumable / disposable products 9. Various near- and medium-term growth opportunities through (i) opening of satellite distribution centers, (ii) expansion of product and service offerings and (iii) potential M&A activity

• 10. Main Street provided 100% of the debt and equity capital needed to close the

transaction

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

3 Page

MAIN (2)

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

4 Page

Company Overview

• Soft Touch Medical (“Soft Touch” or the “Company”) is the leading

home provider of durable medical equipment primarily serving pediatric patients across the state of Georgia.

• The Company was founded in Marietta, GA, in 1997 to address the

needs of the increasing amount of patients receiving home healthcare.

• Soft Touch carries a complete inventory of durable medical equipment

(“DME”) and many disposable supplies.

• In addition to DME, the Company provides patients with enteral

therapy equipment, respiratory machines and other pediatric monitors.

• Soft Touch is known for its outstanding customer service and quick

turnaround delivery times.

• The Company offers 24/7 delivery, setup and instruction of its

products and employs highly trained respiratory therapists.

• The Company offers Spanish interpreters at both the technician

and front office levels, allowing it to support a greater patient base.

• Soft Touch operates in three locations – Marietta, GA (opened in 1997);

Macon, GA (2015); and Savannah, GA (2016) – with near-term plans to expand into adjacent states.

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

5 Page

Referral Sources

“At Children's [Healthcare of Atlanta], we know kids aren't simply tiny adults. They need specialized pediatric care. Our team makes sure your child is comfortable and happy while in our care. We're committed to making all kids better today and healthier tomorrow.”

Marietta, GA Macon, GA

• Hospitals – Working directly with the various

case managers at hospitals across Georgia who have autonomy when referring pediatric patients

• Primary Referral Sources:
• Children’s Healthcare of Atlanta
• Utilized the Company’s delivery

services for ~15 years

• Provider of ~80% of all pediatric

services in the Atlanta metropolitan area

• More than 30 independent case

managers across the CHOA network

• Children’s Hospital Navicent Health
• Primary hospital in the Macon region

with 66 beds and a growing need for in home health services

• Memorial Hospital Savannah, GA
• Leading children’s hospital in the

fastest growing city in Georgia Savannah, GA

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

6 Page

Payor Mix

Pre-Closing Current

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

7 Page

Relationships with Industry Leading Suppliers

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

8 Page

Expanded Coverage Area

Soft Touch has grown to cover the majority of the state of Georgia and has near-term plans to expand further throughout the state and into Alabama, Tennessee and South Carolina.

Long-standing relationship with four location hospital system, Children’s Healthcare of Atlanta (25 counties) Bridged the gap between northwest and southeast Georgia and facilitated a strong relationship with The Children’s Hospital Naviscent Health (30 counties) Has become the preferred pediatric DME provider at Savannah’s Memorial Hospital in less than one year and extended coverage area into South Carolina market (19 counties)

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

9 Page

Product Overview – Enteral

• Enteral feeding products provide patients

the ability to receive necessary nutrition during treatment of temporary acute conditions or permanent chronic disabilities.

• Enteral feeding products provided by the

Company include:

• Portable feeding pumps
• Feeding pump backpacks
• Nutrition pumps
• Gastric (“G-Tube”) supplies
• Nasogastric (“NG-Tube”) supplies

Clinical Nutrition Feeding Pump G-Tube NG-Tube Nutrition Pump Feeding Pump Backpack Infant Formula

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

10 Page

BiPAP Equipment

Product Overview – Respiratory Equipment & Ventilators

• The Company offers respiratory and

advanced respiratory care equipment. These products require significant in-home setup and education for the patient and their guardian.

• Key respiratory care products include:
• Oxygen systems
• Concentrators
• Nebulizers
• Suction machines and pulse oximeters
• Advanced respiratory care products include:
• Intrapulmonary percussive ventilators

(“IPV Units”)

• Continuous (“CPAP”) and Bi-level

(“BiPAP”) Positive Airway Pressure machines

• Heated humidification systems
• Wireless modems for compliance
• Cough assists

CPAP Equipment Oxygen Concentrator IPV Unit Cough Assist

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

11 Page

Product Overview – Infant Monitors & Phototherapy

• Soft Touch provides infant monitors that track

the respiratory systems of babies in the home.

• Also known as apnea monitors, these

products detect any pauses in breathing or decreases in oxygen levels.

• The Company’s primary apnea monitor

products include:

• Smart Monitor II – a lightweight portable

monitor that sounds an alarm upon any respiratory changes and records up to 2 MB of memory to document patient conditions for an extended period of time

• 2PS Apnea Monitor – a detector of heart

rate, oxygen level and respiration changes in a patient primarily used to document patient responses to sedation and treatment

• Bilibeds provide intensive phototherapy for

newborn jaundice.

Smart Monitor II 2 PS Apnea Monitor Bilibed for Jaundice

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

12 Page

Product Overview – Durable Medical Equipment

• Pediatric durable medical equipment

supports patients’ manual and powered movement around the home.

• Pediatric wheelchairs are designed to fit

smaller body weights and sizes than traditional wheelchairs.

• Other DME products include:
• Walkers
• Crutches
• Beds
• CPM
• Bathroom safety equipment
• Transfer aids
• Larger DME is typically provided as rental

equipment and is offered as a complementary product to other respiratory and enteral equipment and supplies.

Four-Wheel Rotator Pediatric Wheelchair Commode Chair Folding Walker Transfer Aids

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

13 Page

“You never think that you are going to have a special needs child. On the same day that we discovered we were to have a son we were told he had something called an Omphalocele. It is an abdominal wall defect. We had no idea what life would be like after he was born. Once he was born he was immediately intubated. Meaning he had to have a breathing tube put down his throat and into his lungs. He was on O2 and had a feeding tube. After being in the NICU for 2.5 months my husband and I decided to have our son trached and we saw his handsome face for the first time. We went home for the first time in August of 2014. He was born in March 2014. We went home in an ambulance with the most amount of machines that any patient could go home with. We were petrified!!! Soft Touch was not the first company we had, but once we switched it made a world of

• difference. We could call and always get an answer or a call back with an
• answer. We love the company and what they stand for. Soft Touch is all

about the patient and what he or she needs. If we run out of O2 it would be delivered that same day or first thing the following morning. If we lose a trach they mail us another. If we discover that we do not need something in

• ur monthly order they discontinue it with no questions asked.

Having a medically fragile child is difficult enough, yet having a company that provides what your child needs makes it much easier to bear.”

• Alison P.

Patient Case Study - Keegan

“Soft Touch was not the first company we had, but once we switched it made a world of

• difference. We could call and

always get an answer or a call back with an answer. We love the company and what they stand for. Soft Touch is all about the patient and what he

• r she needs.”

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

14 Page

MAIN Historical Timeline and Valuations

Q3 2014 Main Street, HMS and management complete recapitalization of Soft Touch for $15.9 million Q3 2015 New location

• pened in

Macon, GA Q3 2016 New location opened in Savannah, GA, expanding the Company’s coverage area into South Carolina

$5.0 $4.9 $4.9 $4.9 $4.9 $4.9 $4.9 $4.9 $4.9 $5.0 $4.9 $5.3 $5.7 $7.5 $8.6 $8.7 $9.2 $9.2

0.0% 100.0% 200.0% 300.0% $0 $3 $5 $8 $10 Dec-14 Jun-15 Sep-15 Dec-15 Mar-16 Jun-16 Sep-16 Dec-16 Mar-17 Equity Cost and FV ($ in millions) Equity Cost ($) Unrealized Appreciation EBITDA Growth % From Original Investment Date Net Debt to EBITDA as a %

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 1

Lower Middle Market Equity

June 2017

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 2

Conservative Historical Nature of MAIN’s Valuations for Equity Investments

EBITDA Multiple

MAIN Weighted Average(1)

7.1x

MAIN Median(1)(2)

6.0x

Other BDC’s – All Equity(3)

7.8x

Industry(4)

8.1x to 8.5x

(1) Source: March 31, 2017 Form 10-Q filing (2) MAIN’s median EBITDA multiple represents the median EBITDA multiple for all equity investments, except investments for which the valuation does not include use of an EBITDA multiple. (3) As published in the most recent Form 10-K or Form 10-Q filed by each BDC as of May 17, 2017. Other BDCs includes 35 BDCs and includes weighted average EBITDA multiples for all forms of equity investments. (4) Source: Overview of Lincoln International Valuations & Opinions Group dated May 2017 as published by Lincoln International. Multiples represent the Total Enterprise Value / Adjusted EBITDA for the Last 12 Months as of December 31, 2016 for all transactions with Total Enterprise Values between (i) $10 million and $30 million (8.1x) and (ii) $30 million to $50 million (8.5x)

MAIN valuation approach and key inputs

– Market-comparable/Historical cash flow approach

• Based on actual MAIN entry transaction multiples, as adjusted over time for overall market and specific company changes
• MAIN EBITDA valuation multiples compare favorably to industry and market valuations:

Two Quarters Prior to Exit Four Quarters Prior to Exit Realized Value at Exit in Comparison to Prior Qtr FV

126% 170%

Realized Value at Exit in Excess of Prior Qtr FV ($ in 000's)

$43,277 $87,244

Exits of LMM equity investments resulting in realized gains have compared positively to previously recorded fair values

– Exits of 27 LMM equity investments with realized gains have resulted in total realized gains of $167 million – Discounted cash flow (DCF) approach

• Weighted average cost of capital (WACC) – significant component of DCF approach is significantly impacted by industry and overall market factors
• These WACC components are obtained from third party sources and can fluctuate significantly from quarter to quarter

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 3

MAIN LMM Strategy Produces Differentiated Returns to Investors

Net Unrealized Appreciation of ~$2.91 per share, or $161 million, from LMM equity investments(1)

(As of March 31, 2017) With Unrealized Appreciation With Unrealized Depreciation % of LMM companies with MAIN Equity Investment

63% 24%

Number of LMM companies with MAIN Equity Investment

45 17

– LMM equity exits have enhanced MAIN’s portfolio returns and provided significant upside, in addition to offsetting the inevitable credit losses occurring from non-investment grade debt investments

• Exits of 27 LMM equity investments resulted in realized gains of $167 million
• Exits of 4 LMM equity investments in 2016 and Q1 2017 resulted in realized gains of $84 million
• Exits of 15 LMM equity investments resulted in realized losses of $15 million
• Net realized losses on exits and restructurings of LMM debt investments of $33 million
• Net realized losses on exits and restructurings of non-LMM debt and equity investments of $43 million
• Cumulative net realized gains across all investment portfolios of $76 million

– Portfolio diversity has resulted in LMM equity investment appreciation across a diverse group of portfolio companies and industries

Equity Exits Enhance MAIN’s Portfolio Returns(2)

(1) As of March 31, 2017 (2) Includes all full exits of LMM equity investments since Initial Public Offering in October 2007 through March 31, 2017

– Remaining Net Unrealized Appreciation at March 31, 2017 is after $84 million of realized gains on the exits of 4 LMM equity investments since December 31, 2015

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 1

Middle Market Update

June 2017

Main Street Capital Corporation NYSE: MAIN www.mainstcapital.com

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 2

Middle Market Debt Investment Strategy

Middle Market Credit Opportunities Private Loans Description

Generally investments in first lien secured loans through primary loan issuance Strategic investments in the secondary market,

• pportunistic purchases,

special situations. Investments in Credit Opportunities will generally be included in the Middle Market portion of MAIN’s investment portfolio. Proprietary investments

• riginated through strategic

relationships with other investment funds on a collaborative basis with attractive risk/return characteristics

Targeted Investments

• First lien secured debt
• Floating rate
• Majority have a B or higher

S&P rating

• First lien secured debt and

high yield bonds

• Ratings agnostic
• Primarily first lien secured

debt

• Primarily floating rate

instruments

• Unrated

Targeted Returns

6-10% gross yields 8-12% gross yields 7-10% gross yields

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 3

Middle Market Assets1

(1) Middle Market only; amounts at fair value

MAIN MAIN MAIN MAIN MAIN HMS HMS HMS HMS HMS I-45 I-45 I-45 $400 $800 $1,200 $1,600 $2,000 2013 2014 2015 2016 1Q '17

$ AUM (Millions)

AUM by Fund

I-45 MAIN HMS L+400 L+500 L+600 L+700 L+800 L+900

Spread by Product

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 4

Portfolio Statistics1, 2

(1) Middle Market held by MAIN (2) Leverage and interest coverage statistics include only borrowing base eligible assets which excludes second lien and other non-eligible assets. $79.0 $68.8 $77.2 $94.1 $98.8 $94.2 $98.6 $95.5

3.94x 3.82x 3.97x 3.50x 3.35x 3.42x 3.41x 3.52x 3.11x 3.07x 3.27x 3.84x 3.47x 3.31x 3.37x 3.15x $0.0 $25.0 $50.0 $75.0 $100.0 $125.0 2.50x 3.00x 3.50x 4.00x 4.50x 5.00x Q4:13 Q2:14 Q4:14 Q2:15 Q4:15 Q1:16 Q4:16 Q1:17

Portfolio Credit Statistics

Portfolio Average EBITDA Portfolio Average Total Net Leverage Ratio Portfolio Average Interest Coverage Ratio

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 5

Consistent Asset Mix 1

(1) Represents Middle Market and Private Loans managed by Middle Market investment team held by MAIN

93.1% 88.4% 87.4% 89.4% 89.2% 6.0% 9.8% 10.8% 9.9% 10.1% 0.9% 1.8% 1.9% 0.7% 0.7% 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 2013 2014 2015 2016 1Q '17

% of Total Portfolio (at Fair Value)

Portfolio Asset Mix

First Lien Second Lien Unsecured

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 6

Middle Market Returns

(1) Total return includes interest, fee and dividend income plus realized and unrealized gains (2) Represents Middle Market and Private Loans managed by Main’s Middle Market investment team held by MAIN

10.31% 4.91% 1.38% 12.12% 13.96% 5.72% 3.46% 4.72% 6.84% 10.39% 7.09% 1.95%

• 0.19%

9.23% 8.86%

• 1.00%

1.00% 3.00% 5.00% 7.00% 9.00% 11.00% 13.00% 15.00% 2013 2014 2015 2016 Q1: 2017

LTM Total Returns1 vs. Indices

MAIN Middle Market² S&P/LSTA U.S. Middle Market Index CS Leveraged Loan Index - B Ratings

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 7

Credit Selection History1

Cumulative Since Inception of MAIN Middle Market Group

(Q2:2009 – Q1:2017)

As of 3/31/2017

~$2,300 / ~300 $62.1 / 9 58.3% Investments Defaults2 Recovery3

Cost / # of Companies ($ in millions)

$588.9 / $568.8 $31.6 / $28.3 89.3%

Cost / FMV

(1) Middle Market assets held by MAIN (2) Includes investments placed on non-accrual plus one distressed credit sale (3) Realized value on defaulted exited investments plus FMV as of 3/31/17 for current investments. Recovery does not include interest income.

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 8

Default Rates

(1) As a percentage of cost of Middle Market assets held by MAIN (2) Includes loans not tracked in the LSTA/LPC mark-to-market service

0.00% 2.00% 2.37% 2.06% 3.50% 1.61% 2.11% 3.24% 1.50% 1.58% 1.43% 2.11% 1.21% 2.82% 3.43% 1.56% 2.05% 2.25% 0.00% 0.50% 1.00% 1.50% 2.00% 2.50% 3.00% 3.50% 4.00% 2013 2014 2015 2016 Q1: 2017 Average 2013 - 2016

LTM Default Rates

MAIN Middle Market¹ S&P/LSTA U.S. Middle Market Index S&P/LSTA U.S. Index²

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 9

Benefits of Middle Market to MAIN

• Return on Equity

– Exceeds MAIN monthly dividend

• Asset Management Business

– Facilitates additional return for MAIN without deploying capital

• Treasury Function

– Repayments provide funding in any market

• Leverage / Debt Structure

– Credit facility would be different without marked assets

• Diversity of Markets

– Ability to pivot between LMM, PL, and MM

• Market Color

– Relationships

FOR INSTITUTIONAL USE ONLY. Not for distribution to the public. Hines Securities, Inc., Member FINRA, SIPC, is the dealer manager. 5/17

This is neither an offer to sell nor a solicitation to buy the securities of HMS Income Fund. An offering is made only by the prospectus. No offering is made in the state of New York in connection with any offering. Neither the Securities and Exchange Commission, the Attorney General of the State of New York nor any other state securities commission has approved

• r disapproved of these securities or determined if the prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

FOR INSTITUTIONAL USE ONLY. Not for distribution to the public. Hines Securities, Inc., Member FINRA, SIPC, is the dealer manager. 5/17

$1 $4 $12 $21 $42 $81 $134 $205 $295 $394 $474 $538 $601 $622 $656 $683 $707 $732 $0 $100 $200 $300 $400 $500 $600 $700 $800 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 2012 2013 2014 2015 2016 2017 $M

1Includes DRIP proceeds.

Historical Capital Raise

Cumulative Gross Proceeds Since Inception1

Offering Period Gross Capital Raised ($M) Initial Offering (closed 12/1/15) $601 Follow-on Offering Through 3/31/17 (opened 1/5/16) 131 Inception through 3/31/17 $732

FOR INSTITUTIONAL USE ONLY. Not for distribution to the public. Hines Securities, Inc., Member FINRA, SIPC, is the dealer manager. 5/17

Portfolio Composition

Asset Class Detail as of 3/31/17

Portfolio holdings are subject to change. 1Weighted average effective yield is calculated based on HMS Income Fund’s investments as of March 31, 2017 and includes accretion of

• riginal issue discounts and amortization of premiums, and the amortization of fees received in connection with transactions. Investments on non-accrual status are assumed to have a

zero yield in the calculation. 2Includes warrants. 3Represents the number of unique portfolio companies. The number of unique portfolio companies is less than the sum of the individual asset class figures because HMS holds both debt and equity investments in select portfolio companies. Data based on fair market value as of March 31, 2017.

($M)

Asset Class Fair Market Value % of Portfolio Portfolio Companies % First Lien of Total Debt Weighted Average Effective Yield1 Middle Market Debt $573.4 59.8% 64 81.6% 8.8% Private Loan Debt 231.9 24.2% 31 94.9% 9.1% Lower Middle Market Debt 82.3 8.6% 23 95.3% 11.9% Middle Market Equity 4.2 0.4% 4

• Private Loan Equity2

5.7 0.6% 7

• Lower Middle Market

Equity2 40.7 4.2% 23

• Other

20.9 2.2% 3

• Total

$959.1 100% 1243 86.4% 8.9%

FOR INSTITUTIONAL USE ONLY. Not for distribution to the public. Hines Securities, Inc., Member FINRA, SIPC, is the dealer manager. 5/17

1Portfolio holdings are subject to change. 2Weighted average effective yield is calculated based on HMS Income Fund’s investments as of March 31, 2017 and includes accretion

• f original issue discounts and amortization of premiums, and the amortization of fees received in connection with transactions. Investments on non-accrual status are assumed to

have a zero yield in the calculation.

3/31/17 Portfolio Highlights

Portfolio Aggregate Fair Market Value $959.1M First Lien Debt as % of Total Debt Fair Market Value 86.4% 124 Portfolio Issuers1

• 118 Debt
• 34 Equity
• 3 Other

Weighted Avg. Effective Yield

• n Investments

(Unlevered)2 8.9%

FOR INSTITUTIONAL USE ONLY. Not for distribution to the public. Hines Securities, Inc., Member FINRA, SIPC, is the dealer manager. 5/17

3/31/17 Portfolio Highlights (cont’d)

1Portfolio holdings and business sector diversification are subject to change. 2Approximately 45% of the portfolio maintains an S&P credit rating. 3Represents borrowing cost under

HMS Income Fund’s credit facilities as of March 31, 2017. Data based on fair market value as of March 31, 2017.

Weighted Avg. Credit Rating2 B Investments on Non-Accrual as % of Fair Market Value 1.1% Industry Diversification1 Leverage

46 Sectors

Top Five Sectors by FMV: Media 8.4% Hotels, Restaurants & Leisure 8.3% Commercial Srvcs. & Supplies 8.1% Construction & Engineering 6.1% IT Services 4.1% Top Five Total 35.0%

41%

3/31/17 Debt ($M): Capacity $480) Less: Borrowings (386) Availability $94) Cost of Capital L+2753

FOR INSTITUTIONAL USE ONLY. Not for distribution to the public. Hines Securities, Inc., Member FINRA, SIPC, is the dealer manager. 5/17

Net Asset Value Per Share

2012 - 3/31/17

$8.86 $8.91 $8.86 $8.85 $8.79 $8.40 $8.57 $8.69 $8.35 $7.88 $7.67 $7.77 $7.92 $8.15 $8.16

$7.50 $7.75 $8.00 $8.25 $8.50 $8.75 $9.00 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 2012 2013 2014 2015 2016 2017

FOR INSTITUTIONAL USE ONLY. Not for distribution to the public. Hines Securities, Inc., Member FINRA, SIPC, is the dealer manager. 5/17

Total Return Comparison

Q3 2012 – Q1 2017

3.2% 1.5% 2.4% 1.2% 2.9% 2.0% 1.4% 1.9% 1.3% (2.4%) 4.1% 3.4% (1.9%) (3.5%) (0.5%) 3.6% 4.2% 5.1% 2.2% 3.4% 1.4% 2.1% 0.2% 1.2% 1.7% 1.2% 1.4% (0.5%) (0.5%) 2.1% 0.7% (1.4%) (2.1%) 1.5% 2.9% 3.1% 2.3% 1.1%

(4.0%) (3.0%) (2.0%) (1.0%) 0.0% 1.0% 2.0% 3.0% 4.0% 5.0% 6.0% Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 2012 2013 2014 2015 2016 2017 HMS Total Return S&P LSTA Total Return

FOR INSTITUTIONAL USE ONLY. Not for distribution to the public. Hines Securities, Inc., Member FINRA, SIPC, is the dealer manager. 5/17

MAIN’s Asset Management Business

Fee Structure

• MAIN1 Base Management Fee – 1%
• MAIN1 Incentive Fee – 10%

Benefits to MAIN

• No significant increases to MAIN’s operating costs
• Utilize existing infrastructure and leverage fixed costs
• No invested capital
• Monetize the value of MAIN franchise
• Impact on MAIN’s financial results:
• $7.9 million to NII2 for 2016
• $2.2 million to NII2 for 1Q2017
• $33.5 million of Cumulative Unrealized Appreciation as of 3/31/17

1 Through MAIN’s wholly owned unconsolidated subsidiary, MSC Advisor I, LLC 2 Contribution to Net Investment Income includes (a) dividend income received by MAIN from MSC Advisor I, LLC and (b) operating expenses allocated from MAIN to MSC Advisor I, LLC

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 1

I-45 Senior Loan Fund

June 2017

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 2

I-45 Senior Loan Fund

Joint Venture formed between MAIN and Capital Southwest1

• Fund invests primarily in 1st lien middle market loans
• Total Equity Commitment of $85 million

– MAIN = $17 million = 20% – CSWC = $68 million = 80%

• Profit distribution split:

– MAIN = 24.4% – CSWC = 75.6% Benefits to MAIN

• Attractive levered equity returns
• “Toe in the water” of Senior Loan Funds
• 22% IRR from Launch to 3/31/17

– 10-12% long term levered yield target I-45 SLF is a stand alone entity with a separate Board of Directors and is accounted for as a portfolio company Utilizes a 50/50 Joint Venture voting structure as seen with other BDCs Created in September 2015

(1) Capital Southwest Corporation (NASDAQ: CSWC)

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 3

I-45 Senior Loan Fund1

Current Portfolio2

• $221.8mm of Assets

– $130.0mm of Debt Outstanding – MAIN has $16.2mm of Equity Invested – ~95% of Committed Equity funded

• 49 Issuers
• 95.2% 1st Lien
• 3.5x Weighted Average Leverage
• $82.1mm Weighted Average EBITDA

Deutsche Bank Leverage Facility

• $165mm Revolver
• 5-year term with 2 year revolving period
• L+275
• Non mark to market
• 66% Max Total Advance Rate (Debt to Assets)

(1) Charts as of December 31, 2016 (2) As of May 16th, 2017

Dale Ford Chief Executive Officer Dwayne L. Hyzak President & Chief Operating Officer Main Street Capital Corporation

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Location

Mountain View, California

Business

Value-added reseller of engineering design and manufacturing software and solutions

Website

www.hawkridgesys.com

Original Investment Date

December 2016

Investment Type

First lien, senior secured loan Minority equity investment

Transaction Type

Minority recapitalization structured to transition Dale Ford, the CEO and minority equity owner, into the majority

• wnership position and

provide full liquidity to inactive equity owners Capital Invested $16.75 million ($12.5 million debt and $3.75 million equity) – 80% MAIN / 20% HMS

Main Street’s View of Transaction and Background

Strong market position and reputation

• With a 20-year history as a value-added reseller (“VAR”) of engineering design and manufacturing software and other

solutions, Hawk Ridge Systems, LLC and HRS Services, ULC (together “Hawk Ridge,” or the “Company”) has developed a strong relationship with its most significant vendor, Dassault Systems (“Dassault”), the publisher of SolidWorks, the world’s leading 3D computer-aided design (CAD) software, and a full suite of other product lifestyle management (PLM) tools.

• Hawk Ridge currently accounts for ~12% of SolidWorks’ North American revenues and is viewed by Dassault’s

management as a leader among its VAR peers. Five times named the world’s top SolidWorks reseller, Dassault often considers Hawk Ridge first when bringing new opportunities to market.

High quality products delivered to a highly diversified customer base

• Hawk Ridge serves 16,000+ customers across a variety of industries, including blue-chip accounts like Google, Apple,

Tesla, Medtronic and Microsoft, with the top customer contributing <2.0% of revenues.

Top-tier customer service through a scalable platform

• Hawk Ridge provides customer service and support at a level beyond other VARs, providing classroom-style and online

training, a database of “How To” videos, real-time remote assistance, analysis consulting and rapid prototyping services.

• Feedback received during Main Street’s due diligence process indicated that customers were particularly pleased with the

depth of technical knowledge, professionalism and responsiveness of Hawk Ridge’s employees.

Significant growth opportunities

• Due to its geographic coverage and the scale of its sales and support team, Hawk Ridge is capable of achieving significant

growth in its core CAD solutions and maintains the opportunity to sell various other PLM tools into its existing customer base.

• Given its historical success completing acquisitions and its desire for continued future growth, Hawk Ridge’s management

team is actively pursuing acquisition opportunities which will allow for significant synergies to be realized due to the established infrastructure already in place at Hawk Ridge.

Alignment with motivated, highly skilled and experienced CEO

• Main Street structured a flexible transaction that allowed for the transfer of ownership control from the Company’s two

inactive equity owners to Dale Ford, the Company’s highly motivated CEO. Ford reinvested 100% of his value from the transaction and is fully aligned with Main Street as the Company’s majority equity owner.

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Diverse and Marquee Customers Value-Added Reseller

Company Overview

• Hawk Ridge is one of North America’s leading providers of engineering design

and manufacturing solutions and professional services

– One of the largest and most efficient sales and marketing organizations, with 180 professionals located across 16 offices throughout the Western U.S. and Canada

• Offering highly technical, widely recognized and acclaimed solutions

– CAD, CAM, CAE software, and 3D printing solutions from market leading vendors like Dassault, Geometric, 3D Systems and HP

• Leveraging deep technical expertise and talent to provide solutions to a diverse

and impressive base of 16,000+ customers

• Market leading software & technology

vendors

• Demonstrated ability to onboard and

ramp new vendors

• Receive and reject constant inquiries for

new vendor additions

• Sales, customer support and services
• Provide CAD, CAM and CAE software,

3D printing and other solutions

• 180 top-tier technical, sales and

marketing professionals

• 16 offices in Western U.S. and Canada
• Deep product and end-market expertise
• 16,000+ Enterprise & SMB customers
• Diverse range of end markets
• Blue-chip customer base with numerous

Fortune 100 strategic accounts Market Leading Vendors

4

Altium / SolidWorks PCB & xBOM (HawkWare)

A history of growth

5

1999 2000 2002 2004 2006 1996 1998

• Founded as a provider of Parametric Technology Corp. (PTC) software solutions

2001 2008 2011 2012 2013 2014 $30 Million $40 Million $50 Million #1 – So. California #2 – No. California #3 – Nevada #4 -- Northwest US

Composer (Dassault) Enterprise PDM (Dassault)

British Columbia Nevada

Workgroup PDM (Dassault) CosmoWorks (now Simulation)

Washington Oregon #5 – Alberta #6 -- Manitoba

3D Systems, Simulia (Dassault) & HawkWare

Ontario

CAMWorks (Geometric) & Electrical (Dassault)

2016 $60 Million Acquisitions New Products Organic Expansion Year Sales 2017 $75 Million

SolidWorks (Dassault)

• Added HP as a 3D printing vendor in May 2017
• Company positioned for continued future growth

Serving large, high-growth markets

• The engineering software market was a

$20.0B industry in 2014 and is expected to grow at an annual rate of 12.2% over the next eight years to $50.4B in 2022

• Hawk Ridge’s primary segments (CAD, CAM

and CAE) represent $15.3B of $20.0B market

Engineering Software 3D Printing

$20.0B $22.4B $25.2B $28.2B $31.7B $35.6B $39.9B $44.8B $50.4B $0.0B $10.0B $20.0B $30.0B $40.0B $50.0B $60.0B 2014 2015 2016 2017 2018 2019 2020 2021 2022 CAD CAE CAM AEC EDA $3.1B $12.8B $21.0B $0.0B $5.0B $10.0B $15.0B $20.0B $25.0B 2013 2018 2020

6

Hawk Ridge serves some of the fastest growing design automation markets and will continue to experience strong, long-term growth as a result of these market dynamics.

• The 3D printing / additive manufacturing market

is expected to rapidly expand from $3.1B in 2013 to $21.0B in 2020

• The industry is exploding and is driven by new

applications in attractive end markets, lower price points for consumer access, and promise

• f mass production for commercial firms

Consumer Energy Healthcare Industrial Technology

Diversified customer base

• Hawk Ridge maintains a highly diversified base of over 16,000 customers

– No end market accounts for more than 18.0% of all accounts

• The Company has limited customer concentration

– Largest customer in 2016 accounted for less than 2.0% of total sales and the top ten customers represented less than 8.0%

• Approximately 1,000 customers are considered “strategic accounts”, possessing

at least five 3D CAD licenses – Strategic accounts comprise 50% of renewal sales and renew at nearly 100%

7

Vendor Annual Sales % Hawk Ridge Sales Length of Relationship Products $3B+ ~85.0% 20 Years $650M+ ~5.0% 4 Years 3D Printers & Materials $50M + 0.0% Established Feb 2016 3D Printers & Materials $48B+ 0.0% Established May 2017 3D Printers & Materials $188M+ ~2.0% 4 Years $60M+ ~8.0%* 5 Years

Relationships with leading vendors

• Hawk Ridge offers a diverse range of solutions from market leading vendors

– Core vendors are expanding and taking share from competitors

• Strong, long-established relationships with its vendors

8

* Includes sales from services and training provided by Hawk Ridge

A long-tenured relationship with Dassault

Key Area Relationship Overview

Revenue Sharing

• Dassault ascribes significant value to its VAR community, providing a favorable

revenue sharing arrangement relative to those of other software vendors

• Revenue sharing arrangements have been altered only once in Hawk Ridge’s

20-year history with Dassault, and Hawk Ridge does not believe this agreement will be revised again due to the time / energy to implement and reseller community pushback Acquisitions

• Dassault has been supportive of continued consolidation among the VAR

community

• Dassault frequently presents Hawk Ridge with acquisition opportunities of
• ther resellers and has historically financed acquisitions for the Company
• Dassault has a right to approve all changes in ownership

Customer Interaction

• Hawk Ridge owns the customer relationship exclusively
• SolidWorks does not sell direct to customers and has utilized this 100%

indirect model since its inception Product Expansion

• Hawk Ridge has free reign to expand its portfolio and offer complementary

solutions to its customers

• Dassault would disapprove of Hawk Ridge offering competing CAD solutions

9

SolidWorks #1 global value-added reseller

• Hawk Ridge is the largest North American SolidWorks value-added reseller

– Accounts for ~5% of global SolidWorks revenue / ~12% of North American revenue

• The Company is the best recognized, awarded and regarded SolidWorks VAR

– Top SolidWorks Reseller five times worldwide, twelve times in North America

• Sterling reputation of customer service and support

– Known for technical sophistication and client focus; 84 dedicated technical professionals

Continuous Recognition as the Leading Provider of SolidWorks Solutions

SolidWorks World Award Number of Wins

Top Reseller – SolidWorks Worldwide 5 Top Reseller – SolidWorks North America 12 Top Reseller – SolidWorks Multi-Product Bookings Worldwide 1 Top Reseller – SolidWorks Multi-Product Licenses Worldwide 1 Top 5 Reseller – SolidWorks Bookings Worldwide 2 Top 5 Reseller – SolidWorks Multi-Product Bookings Worldwide 1 Top 5 Reseller – SolidWorks Multi-Product Licenses Worldwide 1 100% Club – Research Licenses 2 President’s Club 15

10

Wide suite of SolidWorks solutions

3D CAD Simulation Enterprise PDM Composer Electrical PCB Year Adopted 1998 2000 2006 2008 2012 2016 3-Year CAGR 8% - 12% 12% - 15% 17% - 22% 10% - 15% 25% - 40% N/A Overview

Comprehensive 3D product design software enabling end-to- end product design capabilities Simulation software for testing product designs in virtual environments prior to manufacturing PDM software providing a secure database for accessing and sharing design files Software enabling the design and production of visual technical communication deliverables Software enables collaborative multi-line and single line electrical system schematic design Software Enables Electrical Engineers to design Printed Circuit Boards

Notable Highlights

Key customer acquisition solution, highly recognizable and well-known Large area of

• pportunity,

limited relative historical focus

• n this solution

Key customer retention solution (nearly 100% renewal among PDM customers) Enabler of key growth trends such as paperless manufacturing Significant growth

• pportunity

similar to 3D CAD a decade ago Significant growth Opportunity Similar to 3D CAD a decade ago.

11

Product Vendor Year Adopted 3-Year CAGR Description 2012 12% - 15 % Complete computer-aided manufacturing and machining software suite 2013 30%-40%* Advanced simulation software suite used to perform complex analyses with advanced physics 2011 N/A Proprietary software to increase efficiency when working within SolidWorks 3D CAD and Enterprise PDM systems

Selling complementary products

• In addition to SolidWorks, Hawk Ridge provides a range of complementary

software solutions to its customers

• The Company has experienced strong traction with the introduction of these
• fferings to date and believes there is significant runway ahead for these solutions

12

* 2-Year CAGR

Training and services

• Hawk Ridge provides training and other services that are complementary to its

software and 3D printing solutions

• The Company has invested substantial resources to scale these offerings

– Expect high-margin training revenue stream to grow 50% in 2017

13 Service Overview Training

• Training courses for both new and experienced users to help them get the most
• ut of their software investment

CAD

• On-demand CAD development, review and assistance for clients needing to

temporarily leverage a deep bench of engineering talent PDM

• PDM implementation, data migration and custom programming services to
• ptimize client PDM processes

Analysis Consulting

• On-demand analysis consulting services from a knowledgeable team bringing

best practices and proven methodologies for design challenges Customized API Development

• Custom API development and assistance services for industry specific

applications which utilize parametric design and analysis Rapid Prototyping

• In-house rapid prototyping services providing access to a broad range of

technologies

Talented management team

• Hawk Ridge possesses an experienced and energized management team which

has driven impressive growth at the Company over the past five years

• The senior leadership team consists of five executives with an average of 18+

years of experience in their respective fields

• Together since 2012, Hawk Ridge’s executives have a combined 45+ years of

tenure with the Company and are deeply committed to its success

Name & Title Hawk Ridge Tenure Relevant Experience Dale Ford, President & Chief Executive Officer 20 years 24 years Chief Revenue Officer 9 years 15 years Vice President of Marketing 7 years 26 years Corporate Controller 3 years 21 years Vice President of Engineering 11 years 14 years

High Quality Senior Leadership Team

14

2015 2019P

New Acct. Repeat Deal Total New Acct. Repeat Deal Total 2D CAD Replacement 32% 12% 44% 20% 10% 30% 3D CAD Replacement 4% 12% 16% 9% 17% 25% 3D CAD Startups 20% 0% 20% 25% 0% 25% Existing Accounts 0% 20% 20% 0% 20% 20%

• Hawk Ridge is driving strong growth in

3D CAD within its existing geographies

• Track record of expanding 3D CAD

market share at a rate nearly 2x the market average

• Tremendous potential remains within

the Company’s existing territories – 85,000+ potential 3D CAD additions

• Driving demand are several key trends:

– 2D CAD Replacement – 3D CAD Replacement – 3D CAD Startups – Existing Accounts Hawk Ridge 3D CAD Market Share 3D CAD Additions by Trend

15

Accelerate growth in existing geographies

10.9% 13.9% 15.0% 16.0% 17.5% 18.5% 19.5% 2012A 2013A 2014A 2015A 2016E 2017P 2018P 2016A

Capture new territory

• SolidWorks VAR market is primed for

consolidation

– Fragmented market, aging owners and a similar model across businesses – Dassault is supportive of acquisitions made by its high-performing VARs

• Hawk Ridge has held discussions with

numerous potential acquisition targets to allow for geographic expansion, several of which are described below

Target Geographies Served

• Est. Sales

Company A Expansion Markets $25M Company B Expansion Markets $45M Company C Existing Markets $10M Company D Existing Markets $3M Company E Expansion Markets $50M Company F Mixed $35M Company G Mixed $10M

Existing Market Expansion Opportunity

16

Penetrate 3D printing market

• Opportunity to earn recurring revenue from

material sales and service contracts in addition to new machine sales

• Hawk Ridge recently invested in a state-of-the-

art 3D printing center to showcase these products (pictured at right)

• Other long-term opportunities include 3D print

services and 3D printer leasing

$0.0M $5.0M $10.0M $15.0M 2015 2016E 2017P 2018P

3D Printing Projections 3D Printing Center

17

• 3D printing is expected to grow at a

30%+ CAGR over the next 7 years – Hawk Ridge expects to reach $15M in 3D printing sales by 2019

• Solutions are complementary to Hawk

Ridge’s software offerings; most 3D printing customers have at least one SolidWorks license

2016A

• Historically, Hawk Ridge offered 3D printers and consumables manufactured by

3D Systems and Markforged, two leading vendors in the 3D printing / additive manufacturing market

• However, in 2017, the Company was approached by HP to be a cornerstone in

its newly-developed reseller channel for the distribution of HP’s newly developed and cutting edge 3D printing technology, which offers customers:

– Superior, consistent output quality with extreme dimensional accuracy and optimal mechanical properties – Breakthrough speed (up to 10x faster than other printers on the market) – Lowest cost-per-part metric opens doors to short-run manufacturing

18

• Acknowledging the value of the technology, the brand

and HP’s reputation, Hawk Ridge accepted as a HP 3D printing solutions reseller in May 2017

• The Company also offers its customers installation,

training, next-day support services and market- leading applications expertise to help customers

• ptimize their 3D printer performance, throughput,

part quality and yield

The cutting edge of 3D printing technology

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 1

Capital Structure

June 2017

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 2

Our Capital Structure(1)

Maintain a conservative capital structure

• Utilize equity offerings for the majority of our capital financing
• Maximize access to beneficial Small Business Investment

Company (SBIC) Debentures

• Opportunistically add other long-term debt financing options
• Maintain a significant revolving credit facility to provide liquidity

between long-term debt and equity financings

• Maintain significant liquidity and maximize duration of debt

maturities Match capital structure with investment assets

• Duration
• Fixed vs Floating

Use conservative leverage to enhance shareholder returns

• Total Debt to NAV of 0.64x as of March 31, 2017(2)
• Total Debt, excluding SBIC debt, to NAV of 0.45x as of March 31,

2017(2)

• Weighted average yield(3) on existing investment portfolio of

10.1% vs weighted average cost of debt(4) capital of 4.2%

(1) As of March 31, 2017 (2) Calculated based upon the par value of debt (3) Weighted Average Yield calculated using the effective interest rates for all debt investments at cost as of March 31, 2017, including amortization of deferred debt origination fees and accretion of original issue discount but excluding fees payable upon repayment of the debt instruments and any debt investments on non-accrual status (4) Weighted Average Cost of Debt calculated utilizing stated interest rate of debt capital and including amortization of deferred financing costs

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% $- $250 $500 $750 $1,000 $1,250 $1,500 $1,750 $2,000 $2,250

(in millions)

RLOC Unfunded Capacity RLOC 5-Year Notes 10-Year Notes SBIC Unfunded Capacity SBIC Debentures Equity

Moderate- term Capital Long-term Capital Permanent Capital

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 3

MAIN (2) Internally Managed BDC’s (3)(5) Externally Managed BDC’s (4)(5)

Long-term Duration of Debt Obligations

MAIN’s conservative capital structure provides long-term access to attractively- priced and structured debt facilities

• Allows for investments

in assets with long- term holding periods / illiquid positions and greater yields and

• verall returns
• Provides downside

protection and liquidity through economic cycles

• Allows MAIN to be
• pportunistic during

periods of economic uncertainty

$288.0 $20.0 $55.0 $40.0 $5.0 $16.0 $63.8 $40.4 $90.7 $175.0

50 100 150 200 250 300 350 400

2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027

(in millions)

Credit Facility SBIC debentures 6.125% Notes 4.50% Notes

(1) (2) (3)

(1) Based upon outstanding balance as of March 31, 2017; total commitments at March 31, 2017 were $555.0 million (2) Issued in April 2013; redeemable at MAIN’s option beginning April 2018 (3) Issued in November 2014; redeemable at MAIN’s option at any time, subject to certain make whole provisions

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 4

Match Funding with Investment Assets(1)

Main Street maintains a capital structure that is designed to match our capital funding with our investment assets

• The term of our capital

sources is matched with the expected hold period of our portfolio investments

(1) As of March 31, 2017; Investment Assets exclude investments in our Other Portfolio and MSC Adviser I, LLC

(1)

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% MAIN's Capital Investments at Cost Investments at FMV (% of total)

Long-term Capital Moderate- term Capital Long-term / illiquid Investments Moderate- term / partially illiquid Investments Permanent Capital

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 5

Match Funding with Investment Assets(1)

Main Street maintains a capital structure that is designed to match our capital funding with our investment assets

• The floating and fixed

rate nature of our debt capital sources are

• pportunistically

matched with the nature of our debt investments

• Provides opportunity

for significant investment income accretion in a rising rate environment, with limited downside

(1) As of March 31, 2017

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% MAIN's Debt Capital Debt Investments at Cost (% of total)

RLOC 5-Year Notes 10-Year Notes SBIC Debt

Fixed Rate Floating Rate

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 6

At-The-Market (ATM) Equity Program

ATM provides permanent capital to match indefinite or long- term holding period for LMM investments ATM facilitates maintenance of conservative leverage position ATM issued equity is accretive to NAV per share ATM provides significant benefits vs traditional overnight equity offerings

• Provides equity capital and liquidity on an as-needed basis, avoiding dilution

from larger overnight equity offerings

• Provides equity capital at significantly lower cost
• Avoids negative impact to stock price from larger overnight equity offerings

Raised net proceeds of approximately $155 million since inception in 2015(1)

• Average sale price of $34.72, or approximately 60% above average NAV per

share over same period(1)

• Resulted in economic cost savings of approximately $7.8 million when

compared to traditional overnight equity offering(2)

ATM Equity Program provides efficient, low cost capital

• Provides permanent

capital to match growth

• f LMM investments on

an as-needed basis

• Provides significant

economic cost savings compared to traditional

• vernight equity
• fferings

(1) Through March 31, 2017 (2) Assumes 6% all-in cost for traditional overnight equity offering

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 7

Direct Stock Purchase Program (DSPP)

In response to consistent requests from our retail shareholder base, MAIN is currently working with our transfer agent to establish a DSPP MAIN should be in a position to launch the DSPP in the third quarter of 2017 Proposed DSPP terms (to be finalized):

• Investors may purchase shares directly from MAIN under the

DSPP

• Investors pay no brokerage or other expenses on such

purchases

• Shares sold monthly in amounts from $100 to $25,000
• Investors can purchase on a one-time or recurring basis
• Plan administered by MAIN’s transfer agent

DSPPs are common for public operating companies, but not for investment companies due to certain regulatory hurdles MAIN would be the only BDC with an active DSPP DSPP will allow long-term investors a low cost option to purchase shares directly from MAIN

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 8

Positive Impact from Rising Interest Rates

Basis Point Increase in Interest Rate Increase in Interest Income Increase in Interest Expense(2) Increase in Net Investment Income Increase in Net Investment Income per Share(5) 25 $ 2,207 $ (720) $ 1,487 $ 0.03 50 4,556 (1,440) 3,116 0.06 100 9,333 (2,880) 6,453 0.12 150 14,163 (4,320) 9,843 0.18 200 19,006 (5,760) 13,246 0.24 300 28,692 (8,640) 20,052 0.36 400 38,406 (11,520) 26,886 0.49

The following table illustrates the approximate annual increase in the components of MAIN’s net investment income due to hypothetical increases in interest rates(1) (dollars in thousands):

MAIN’s capital structure and investment portfolio provides downside protection and the

• pportunity for significant benefits

from a rising interest rate environment

• 64% of MAIN’s outstanding debt
• bligations have fixed interest rates(3),

limiting the potential increase in interest expense

• 65% of MAIN debt investments bear

interest at floating rates(3), the majority

• f which contain contractual minimum

index rates, or “interest rate floors” (weighted-average floor of approximately 105 basis points)(4)

• Provides MAIN the opportunity to

achieve significant increases in net investment income if interest rates rise

(1) Assumes no changes in the portfolio investments, outstanding revolving credit facility borrowings or other debt obligations existing as of March 31, 2017 (2) The hypothetical increase in interest expense would be impacted by the changes in the amount of debt

• utstanding under our revolving credit facility, with interest expense (increasing) decreasing as the debt
• utstanding under our revolving credit facility increases (decreases)

(3) As of March 31, 2017 (4) Weighted-average interest rate floor calculated based on debt principal balances as of March 31, 2017 (5) Per share amount is calculated using shares outstanding as of March 31, 2017

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 9

Basis Point Increase in Interest Rate Increase in Interest Income Increase in Interest Expense(3) Increase in Net Investment Income 50 3,573 (1,930) 1,643 100 7,448 (3,860) 3,588 200 15,232 (7,720) 7,512 300 23,019 (11,580) 11,439

Positive Impact from Rising Interest Rates (continued)

The following table illustrates the approximate annual increase in the components of HMS’ net investment income due to hypothetical increases in interest rates(2) (dollars in thousands):

Rising interest rates provide potential upside to incentive fees from our asset management business through MAIN’s(1) investment sub-advisory agreement with the investment advisor to HMS Income Fund,

• Inc. (HMS), a non-listed BDC
• MAIN(1) receives 50% of the

investment advisor’s base management fee and incentive fees – MAIN(1) base management fee – 1% of total assets – MAIN(1) incentive fees – 10%

• f net investment income

above a hurdle and 10% of net realized capital gains

(1) Through MAIN’s wholly owned unconsolidated subsidiary, MSC Advisor I, LLC (2) Obtained from the HMS Income Fund, Inc. quarterly report on Form 10-Q for the quarter ended March 31, 2017; assumes no changes in the portfolio investments, the outstanding revolving credit facility borrowings or

• ther debt obligations existing as of March 31, 2017

(3) The hypothetical increase in interest expense would be impacted by the changes in the amount of debt

• utstanding under their revolving credit facilities, with interest expense (increasing) decreasing as the debt
• utstanding under their revolving credit facilities increases (decreases)

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 1

Future Outlook

June 2017

Main Street Capital Corporation NYSE: MAIN mainstcapital.com

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 2

5 Year Strategic Overview – Portfolio Growth

Continue to execute on differentiated Lower Middle Market (LMM) strategy

• Continue to focus on growth of LMM investments
• LMM investments targeted to constitute approximately 50% of total

investment portfolio (approximately 45% at March 31, 2017 at fair value)

• Continue to make meaningful equity investments in LMM companies (20% to

30% of capital invested in each new investment)

• Opportunistically recycle capital currently invested in specific companies

where the existing investments and/or portfolio companies are not delivering

• n MAIN’s key value drivers

– Investments with limited dividend income on equity investments – Investments with lack of visible opportunities for future equity value appreciation – Smaller size investments

• Maintain long-term to permanent holding period for select investments,

resulting in more diverse and higher quality investment portfolio long-term

• Increased focus on opportunities to invest in existing portfolio companies

(acquisitions and organic expansion)

• Benefit from increased dividend income and NAV per share appreciation

(unrealized equity appreciation) as equity investments mature

• Increase LMM market penetration – significantly increase number of LMM

investment professionals, with total number of MAIN employees of approximately 100 by the end of 2021

MAIN’s 5 Year Plan is the result of annual strategic planning process between MAIN’s executive management team and MAIN’s Board of Directors Primary focus remains on growing Lower Middle Market Portfolio

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 3

5 Year Strategic Overview – Portfolio Growth (continued)

Continue growth in Private Loan (PL) portfolio

• Attractive debt investments due to higher yield and increased control over

capital structure when compared to syndicated Middle Market (MM) debt investments

• PL investments targeted to constitute approximately 20% of total investment

portfolio (approximately 19% at March 31, 2017 at fair value)

Continue to use MM debt investments to enhance investment income and to mitigate the effect of the “lumpy” nature of LMM investment returns

• Grow MM debt investments at steady pace through the end of 2021
• MM debt investments targeted to constitute approximately 25% of total

investment portfolio (approximately 29% at March 31, 2017 at fair value)

MAIN’s 5 Year Plan is the result of annual strategic planning process between MAIN’s executive management team and MAIN’s Board of Directors Maintain complimentary benefits from Private Loan and Middle Market investment portfolios

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 4

5 Year Strategic Overview – Capital Structure

Continue to diversify capital structure

• Utilize maximum permitted amount of attractive Small Business Investment

Company (SBIC) debentures ($350 million) – Long-term, low cost capital not subject to regulatory leverage limits

• Maintain industry’s top investment grade debt rating and issue investment

grade notes to maintain low cost of capital and debt maturities that match profile of portfolio investments

• Maintain attractive revolving credit facility to ensure adequate liquidity and to

fund MM debt investments

• Continue effective use of low cost and efficient ATM equity offerings to

maintain optimal liquidity and conservative leverage

Conservatively operate within S&P targeted leverage metrics and regulatory leverage limits

• Leverage target of debt, excluding SBIC debentures, to equity of

approximately 0.50x to 0.60x at end of 2021 – Significant cushion to S&P’s desired target of less than 0.85x

• Debt to Adjusted Total Equity (equity excluding cumulative unrealized

appreciation) of less than 1.0x – Significant cushion to S&P’s desired target of less than 1.5x

• Maintain conservative cushion under regulatory BDC asset coverage at

>2.5x at the end of 2021

Maintain conservative leverage and low cost, diversified capital structure

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 5

Other Strategic Initiatives

Continue to seek growth opportunities in Asset Management business

• Continued focus on opportunities with HMS relationship
• Management of other Middle Market Loan Funds
• Management of “non-core” investment funds (mezzanine debt, larger

middle market debt, etc.) Monitor opportunities for strategic mergers and acquisitions (M&A) and be opportunistic if available

• The BDC industry is evolving
• Shareholder expectations are increasing
• Both factors should continue to increase M&A opportunities in the

future Explore other strategic initiatives to enhance shareholder returns

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 6

5 Year Strategic Overview –Conservative Dividend Policy

Continue to grow Distributable Net Investment Income (DNII) primarily through portfolio growth and continued leverage of efficient operating structure

• Grow total investment income (at a minimum) in line with growth in

total investment portfolio

• Maintain strong total investment income to DNII conversion (i.e.
• perating margins) through efficient operating costs and limited and

attractively priced leverage

• Maintain conservative dividend policy with monthly dividends per

share at less than 95% of DNII per share on annual basis

• Continue long-term moderate growth of the MAIN monthly dividend

Continue to leverage efficient internally managed cost structure

• Maintain low operating costs, excluding interest expense, as a

percentage of total assets at 1.75% or less

• Maintain efficiency ratio of approximately 20% or less

Consider and evaluate opportunities to retain capital long-term when appropriate

• Potential benefits from tax structuring and planning
• Cost comparison of retaining capital vs supplemental dividend

payments and continued equity offerings

Maintain conservative dividend policy with monthly dividend set at less than 95% of DNII

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Page 7

5 Year Strategic Overview – Maintain Superior Shareholder Returns

Differentiated strategy will maintain superior shareholder returns

• Maintain long-term Return on Equity of low to high teens

(averaging low to mid teens over five year period)

• Stock price appreciation due to continued moderate growth in

monthly dividends and increases in NAV per share

• Target total annual return to shareholders of 10% to 15% annually
• Consistent with historical returns, we believe these results would

compare very favorably specifically to other yield oriented investment options and to other publicly traded companies generally Other strategic initiatives provide opportunity for additional returns to shareholders as such opportunities arise Successful strategy execution should result in continued superior returns to MAIN shareholders

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

MAIN (2)

Brian Wagner

President and CEO

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

Main Street’s View of Transaction and Background

1. Gamber was owned by Leggett & Platt as an independently-operated subsidiary that was non-core to the corporate strategy leaving the Management team with minimal capex and operating flexibility. 2. Main Street partnered with the Management team to acquire Gamber and has since increased re-investment into the business and empowered the Management to operate the business with the goal to maximize value. 3. High free cash flow characteristics with gross margins of ~44% driven by Lean Manufacturing operations. 4. Well diversified customer base consisting of blue chip, rugged computer and tablet OEMs. 5. High barriers to entry due to proprietary IP and OEM certification process. 6. Various near term growth opportunities exist with (i) new OEM partners (ii) international expansion, and (iii) new product launches. 7. Sophisticated and driven Management team able to execute on various initiatives, including two acquisitions completed to date. 8. Attractive alignment of interest through Management’s direct cash equity investments and granted incentive equity that did not previously exist under Leggett & Platt. 9. Main Street provided 100% of the debt and majority of the equity needed to close the transaction and subsequent acquisitions.

Locations: Stevens Point, WI (headquarters) Calgary, Canada Umea, Sweden Business: Manufacturer of ruggedized docks and mounting systems for electronics Website: www.gamberjohnson.com www.zirkona.com www.precisionmounts.com Original Investment Date: June 24th, 2016 Investment Type:

• First lien, senior secured term loan
• Revolver commitment
• Majority equity co-investment

Transaction Type: Management buyout / Leveraged buyout Capital Invested: $48.7 million ($30.1 million debt and $18.6 million equity) – 80% MAIN / 20% HMS

Main Street Capital Corporation Analyst Day – June 9, 2017

Brian Wagner

President and CEO Gamber-Johnson LLC

• Gamber,

founded in 1954, manufactures docks and mounts to secure rugged and non-rugged mobile computers, tablets and

• ther equipment to professional

vehicles used in a variety of industries where connectivity and durability are

• f

utmost importance.

• The Company offers a broad

range of products and prides itself

• n

the following core competencies.

– Safety & Stability – Customer Service – Product Reliability – Ergonomics & Functionality – Innovation & Engineering

• Management has been with the

Company, on average, over 10 years and four managers have been with the Company prior to Leggett & Platt’s acquisition of Gamber in 2007.

Product Examples End Market Distribution

Public Safety Commercial Material Handling/Other ~ 48% of Sales ~ 46% of Sales ~ 6% of Sales

Company Overview

• Gamber is one of only two OEM

certified manufacturers of rugged docking solutions from Panasonic, Getac, and Dell in the U.S. and Canada.

• Gamber utilizes six sigma, 5S and
• ther

lean manufacturing techniques for streamlined processes.

• The

Company’s products are primarily sold through its OEMs and its reseller distribution network.

• Gamber’s docks and mounts are

utilized by professionals in highly demanding, mission critical work environments. These professionals rely on Gamber to provide systems of the highest quality and structural integrity.

Company Overview Cont’d

5

Company Timeline

1954 1976 1982 1994 1998 1999 2004 2006 2007 2008 2012 2014 2015 2016

Gamber founded in Stevens Point, WI Larsen Electronics acquired Gamber Introduced Slide Mount product Introduced the NotePad; industry’s first universal laptop mount Acquired Onsite Instruments Start of Panasonic OEM partnership Acquired Scientific Dimensions Gautam Malik joins Gamber as Director of Operations to roll out its lean initiative Start of Getac OEM partnership Acquired by L&P Brian Wagner joins Gamber as President Introduced TabCruzer Introduced rugged tablets for Getac, including a new medical tablet Start of Zebra OEM partnership for forklift applications Launch of international sales efforts in UK, UAE, Brazil Expanded international sales initiatives

Under Prior Private Ownership L&P Ownership MAIN / Management Ownership

Initiation of OEM relationship with Dell. Main Street acquires Gamber-Johnson in June 2016 Gamber acquires Zirkona in December 2016 Gamber acquires PMT in January 2017

2017

Illustrative Product Portfolio

Base Pole Motion Attachment Console Box Material Handling Keyboard Mount Printer Mount Laptop Dock Tablet Dock

Technological advancements and a limited useful life of laptops & tablets drive sales

Product Overview

Mate terial rial handling ling

Forklif rklifts ts

Pu Publi lic c sa safet ety

Police lice cars Fi Fire e tr truc ucks ks Amb mbulances ulances

Ente terprise prise

Trucks ucks Vans ns Sem emis

Growth Initiatives

• The Company has begun multiple initiatives to promote growth:

— International initiatives in Europe, India, Brazil — New OEM relationship with Dell — Gamber rebranded its marketing materials and all products — Two acquisitions since close

Rebranding:

Umea, Sweden

Gamber acquired the Zirkona in December 2016 for its IP and unique ball-in-joint products Produces flexible mounting systems, which supplement Gamber’s tablet docks, providing a less-bulky mounting alternative for light-weight electronics Manufactures aluminum MAX3 product line For vehicles, homes, buses, helicopters, etc.

Calgary, Canada

Gamber acquired Precision Mounting Technologies (PMT) in January 2017 Expanded the Company’s market reach & presence in Canada and acquired key customer relationships Manufactures aluminum consoles and docking stations Smaller and lighter design, allowing for more space in a vehicle Manufactured in-house

mainstcapital.com NYSE: MAIN Main Street Capital Corporation

MAIN Historical Timeline and Valuations

$12.1 $14.8 $14.8 $12.1 $18.9 $22.1

0% 100% 200% 300% 400% $10 $12 $14 $16 $18 $20 $22 $24 Jun-16 Dec-16 Mar-17 (Net Debt and EBITDA Growth - As a %) Equity Cost and FV ($ in millions) Equity Cost ($) Unrealized Appreciation EBITDA Growth % From Original Investment Date Net Debt to EBITDA as a %

A – Q2 2016 MAIN and its co-investor complete LBO/MBO (A)

2016 2017

(B) (C) B – Q4 2016 Gamber completes its acquisition of Zirkona C – Q1 2017 Gamber completes its acquisition of PMT