Quarterly report [Sections 13 or 15(d)]

FAIR VALUE HIERARCHY FOR INVESTMENTS???PORTFOLIO COMPOSITION (Tables)

v3.25.1
FAIR VALUE HIERARCHY FOR INVESTMENTS—PORTFOLIO COMPOSITION (Tables)
 3 Months Ended
Mar. 31, 2025
Fair Value Disclosures [Abstract]  
Schedule of Fair Value Measurement Inputs and Valuation Techniques
The following tables provide a summary of the significant unobservable inputs used to fair value Main Street’s Level 3 portfolio investments as of March 31, 2025 and December 31, 2024:
Type of
Investment
Fair Value as of
March 31, 2025
(in thousands)
 Valuation Technique Significant Unobservable Inputs Range (4) Weighted-Average (4)(5) Median (4)
Equity investments $ 1,716,670  Discounted cash flow WACC
9.6% - 22.7%
 14.4  % 15.0  %
Market comparable / Enterprise value EBITDA multiple (1) (3)
5.0x - 8.9x (2)
 7.4x 6.5x
Debt investments $ 3,272,588  Discounted cash flow Risk adjusted discount rate (6)
8.9% - 17.8% (2)
 12.3  % 12.3  %
Expected principal recovery percentage
0.0% - 500.0%
 99.5  % 100.0  %
Debt investments $ 43,369  Market approach Third-party quote
14.5 - 100.3
 88.8 86.3
Total Level 3 investments $ 5,032,627 
___________________________
(1)EBITDA may include proforma adjustments and/or other add-backs based on specific circumstances related to each investment.
(2)Range excludes outliers that are greater than one standard deviation from the mean. Including these outliers, the range for EBITDA multiple is 2.0x - 16.0x and the range for risk adjusted discount rate is 5.0% - 36.2%.
(3)The fair value of the equity investment in the External Investment Manager is based on a fee multiple of 8.0x. The fair value determination is based on a discounted, blended multiple based on the multiples for similar businesses in active markets and actual multiples used in private transactions.
(4)Does not include investments for which the valuation technique does not include the use of the applicable fair value input.
(5)Weighted-average is calculated for each significant unobservable input based on the applicable security’s fair value.
(6)Discount rate includes the effect of the standard SOFR base rate, as applicable.
Type of Investment
Fair Value as of December 31, 2024
(in thousands)
 Valuation Technique Significant Unobservable Inputs Range (4) Weighted-Average (4)(5) Median (4)
Equity investments $ 1,654,304  Discounted cash flow WACC
9.4% - 22.5%
 14.5  % 15.1  %
Market comparable / Enterprise value EBITDA multiple (1) (3)
4.8x - 8.9x (2)
 7.0x 6.5x
Debt investments $ 3,174,745  Discounted cash flow Risk adjusted discount rate (6)
8.5% - 19.1% (2)
 12.6  % 12.2  %
Expected principal recovery percentage
0.0% - 100.0%
 99.5  % 100.0  %
Debt investments $ 103,620  Market approach Third-party quote
21.0 - 100.7
 90.5 84.5
Total Level 3 investments $ 4,932,669 
___________________________
(1)EBITDA may include proforma adjustments and/or other add-backs based on specific circumstances related to each investment.
(2)Range excludes outliers that are greater than one standard deviation from the mean. Including these outliers, the range for EBITDA multiple is 2.0x - 17.0x and the range for risk adjusted discount rate is 5.0% - 38.3%.
(3)The fair value of the equity investment in the External Investment Manager is based on a fee multiple of 8.5x. The fair value determination is based on a discounted, blended multiple based on the multiples for similar businesses in active markets and actual multiples used in private transactions.
(4)Does not include investments for which the valuation technique does not include the use of the applicable fair value input.
(5)Weighted-average is calculated for each significant unobservable input based on the applicable security’s fair value.
(6)Discount rate includes the effect of the standard SOFR base rate, as applicable.
Schedule of Changes in Fair Value of Main Street’s Level 3 Portfolio Investments
The following tables provide a summary of changes in fair value of Main Street’s Level 3 portfolio investments for the three months ended March 31, 2025 and 2024 (amounts in thousands):
Type of Investment
Fair Value
as of
December 31, 2024
 Transfers Out of Level 3 Hierarchy Redemptions/ Repayments New Investments Net Changes from Unrealized to Realized Net Unrealized Appreciation (Depreciation) Other (1)
Fair Value
as of
March 31, 2025
Debt $ 3,278,365  $ —  $ (179,192) $ 222,305  $ 30,440  $ (8,711) $ (27,250) $ 3,315,957 
Equity 1,637,181  (16,810) (12,868) 23,679  (1,532) 37,887  27,250  1,694,787 
Equity Warrant 17,123  —  —  —  —  4,760  —  21,883 
$ 4,932,669  $ (16,810) $ (192,060) $ 245,984  $ 28,908  $ 33,936  $ —  $ 5,032,627 
___________________________
(1)Includes the impact of non-cash conversions. These transactions represent non-cash investing activities. See additional cash flow information in the Consolidated Statements of Cash Flows.
Type of Investment
Fair Value
as of
December 31, 2023
 Transfers Into Level 3 Hierarchy Redemptions/ Repayments New Investments Net Changes from Unrealized to Realized Net Unrealized Appreciation (Depreciation) Other (1)
Fair Value
as of
March 31, 2024
Debt $ 2,883,917  $ —  $ (158,527) $ 260,765  $ 4,075  $ (12,080) $ 18,859  $ 2,997,009 
Equity 1,395,744  —  (14,509) 30,534  7,079  41,136  (18,859) 1,441,125 
Equity Warrant 6,610  —  —  —  —  (100) —  6,510 
$ 4,286,271  $ —  $ (173,036) $ 291,299  $ 11,154  $ 28,956  $ —  $ 4,444,644 
___________________________
(1)Includes the impact of non-cash conversions. These transactions represent non-cash investing activities. See additional cash flow information in the Consolidated Statements of Cash Flows.
Schedule of Portfolio Investments by Level in the Fair Value Hierarchy
As of March 31, 2025 and December 31, 2024, Main Street’s investments at fair value were categorized as follows in the fair value hierarchy for ASC 820 purposes:
Fair Value Measurements
(in thousands)
As of March 31, 2025
 Fair Value Quoted Prices in
Active Markets for
Identical Assets
(Level 1)		 Significant Other
Observable Inputs
(Level 2)		 Significant
Unobservable
Inputs
(Level 3)
LMM portfolio investments $ 2,610,960  $ —  $ —  $ 2,610,960 
Private Loan portfolio investments 1,942,178  —  —  1,942,178 
Middle Market portfolio investments 128,317  —  —  128,317 
Other Portfolio investments 134,514  21,512  —  113,002 
External Investment Manager 238,170  —  —  238,170 
Total investments $ 5,054,139  $ 21,512  $ —  $ 5,032,627 
Fair Value Measurements
(in thousands)
As of December 31, 2024
 Fair Value Quoted Prices in
Active Markets for
Identical Assets
(Level 1)		 Significant Other
Observable Inputs
(Level 2)		 Significant
Unobservable
Inputs
(Level 3)
LMM portfolio investments $ 2,502,872  $ —  $ —  $ 2,502,872 
Private Loan portfolio investments 1,904,324  —  —  1,904,324 
Middle Market portfolio investments 155,329  —  —  155,329 
Other Portfolio investments 124,144  —  —  124,144 
External Investment Manager 246,000  —  —  246,000 
Total investments $ 4,932,669  $ —  $ —  $ 4,932,669 
Schedule of Investment Holdings
The following tables provide a summary of Main Street’s investments in the LMM and Private Loan portfolios as of March 31, 2025 and December 31, 2024 (this information excludes Middle Market, Other Portfolio investments and the External Investment Manager, which are discussed further below).
As of March 31, 2025
LMM (a) Private Loan
(dollars in millions)
Number of portfolio companies 86  90 
Fair value $ 2,611.0  $ 1,942.2 
Cost $ 1,996.2  $ 1,986.0 
Debt investments as a % of portfolio (at cost) 70.7  % 94.7  %
Equity investments as a % of portfolio (at cost) 29.3  % 5.3  %
% of debt investments at cost secured by first priority lien 99.2  % 99.9  %
Weighted-average annual effective yield (b) 12.7  % 11.4  %
Average EBITDA (c) $ 10.5  $ 32.6 
___________________________
(a)As of March 31, 2025, Main Street had equity ownership in all of its LMM portfolio companies, and the average fully diluted equity ownership in those portfolio companies was 39%.
(b)The weighted-average annual effective yields were computed using the effective interest rates for all debt investments as of March 31, 2025, 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, and are weighted based upon the principal amount of each applicable debt investment as of March 31, 2025. The weighted-average annual effective yield on Main Street’s debt portfolio as of March 31, 2025, including debt investments on non-accrual status, was 12.1% for its LMM portfolio and 10.8% for its Private Loan portfolio. The weighted-average annual effective yield is not reflective of what an investor in shares of Main Street’s common stock will realize on its investment because it does not reflect changes in the market value of Main Street’s stock, Main Street’s utilization of debt capital in its capital structure, Main Street’s expenses or any sales load paid by an investor.
(c)The average EBITDA is calculated using a simple average for the LMM portfolio and a weighted-average for the Private Loan portfolio. These calculations exclude certain portfolio companies, including six LMM portfolio companies and seven Private Loan portfolio companies, as EBITDA is not a meaningful valuation metric for Main Street’s investments in these portfolio companies, and those portfolio companies whose primary purpose is to own real estate and those portfolio companies whose primary operations have ceased and only residual value remains.
As of December 31, 2024
LMM (a) Private Loan
(dollars in millions)
Number of portfolio companies 84  91 
Fair value $ 2,502.9  $ 1,904.3 
Cost $ 1,937.8  $ 1,952.5 
Debt investments as a % of portfolio (at cost) 70.8  % 95.4  %
Equity investments as a % of portfolio (at cost) 29.2  % 4.6  %
% of debt investments at cost secured by first priority lien 99.2  % 99.9  %
Weighted-average annual effective yield (b) 12.8  % 11.8  %
Average EBITDA (c) $ 10.2  $ 30.5 
___________________________
(a)As of December 31, 2024, Main Street had equity ownership in all of its LMM portfolio companies, and the average fully diluted equity ownership in those portfolio companies was 38%.
(b)The weighted-average annual effective yields were computed using the effective interest rates for all debt investments as of December 31, 2024, 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, and are weighted based upon the principal amount of each applicable debt investment as of December 31, 2024. The weighted-average annual effective yield on Main Street’s debt portfolio as of December 31, 2024, including debt investments on non-accrual status, was 12.3% for its LMM portfolio and 11.5% for its Private Loan portfolio. The weighted-average annual effective yield is not reflective of what an investor in shares of Main Street’s common stock will realize on its investment because it does not reflect changes in the market value of Main Street’s stock, Main Street’s utilization of debt capital in its capital structure, Main Street’s expenses or any sales load paid by an investor.
(c)The average EBITDA is calculated using a simple average for the LMM portfolio and a weighted-average for the Private Loan portfolio. These calculations exclude certain portfolio companies, including five LMM portfolio companies and five Private Loan portfolio companies, as EBITDA is not a meaningful valuation metric for Main Street’s investments in these portfolio companies, and those portfolio companies whose primary purpose is to own real estate and those portfolio companies whose primary operations have ceased and only residual value remains.
The following tables summarize the composition of Main Street’s total combined LMM, Private Loan and Middle Market portfolio investments at cost and fair value by type of investment as a percentage of the total combined LMM, Private Loan and Middle Market portfolio investments, as of March 31, 2025 and December 31, 2024 (this information excludes Other Portfolio investments and the External Investment Manager, which are discussed above).
Cost: March 31, 2025 December 31, 2024
First lien debt 82.2  % 82.9  %
Equity 17.2  16.4 
Second lien debt 0.1  0.2 
Equity warrants 0.3  0.3 
Other 0.2  0.2 
100.0  % 100.0  %
Fair Value: March 31, 2025 December 31, 2024
First lien debt 70.4  % 71.4  %
Equity 28.9  27.8 
Second lien debt 0.1  0.2 
Equity warrants 0.4  0.4 
Other 0.2  0.2 
100.0  % 100.0  %
The following tables summarize the composition of Main Street’s total combined LMM, Private Loan and Middle Market portfolio investments by geographic region of the United States and other countries at cost and fair value as a percentage of the total combined LMM, Private Loan and Middle Market portfolio investments, as of March 31, 2025 and December 31, 2024 (this information excludes Other Portfolio investments and the External Investment Manager). The geographic composition is determined by the location of the corporate headquarters of the portfolio company.
Cost: March 31, 2025 December 31, 2024
West 24.5  % 25.1  %
Midwest 22.9  22.7 
Northeast 20.4  21.2 
Southwest 19.2  16.7 
Southeast 10.3  11.6 
Canada 1.3  1.3 
Other Non-United States 1.4  1.4 
100.0  % 100.0  %
Fair Value: March 31, 2025 December 31, 2024
Midwest 24.8  % 24.2  %
West 23.6  24.1 
Southwest 22.4  20.1 
Northeast 17.9  19.4 
Southeast 9.0  9.7 
Canada 1.1  1.2 
Other Non-United States 1.2  1.3 
100.0  % 100.0  %
Main Street’s LMM, Private Loan and Middle Market portfolio investments are in companies conducting business in a variety of industries. The following tables summarize the composition of Main Street’s total combined LMM, Private Loan and Middle Market portfolio investments by industry at cost and fair value as of March 31, 2025 and December 31, 2024 (this information excludes Other Portfolio investments and the External Investment Manager).
Cost: March 31, 2025 December 31, 2024
Machinery 9.1  % 9.2  %
Internet Software & Services 6.7  7.1 
Commercial Services & Supplies 5.5  5.5 
Professional Services 5.4  5.4 
Electrical Equipment 5.2  3.9 
Health Care Providers & Services 4.6  4.3 
Auto Components 4.2  4.0 
Diversified Consumer Services 4.2  4.3 
Distributors 4.1  4.0 
Containers & Packaging 4.0  3.8 
IT Services 4.0  4.1 
Construction & Engineering 3.4  3.8 
Energy Equipment & Services 2.9  2.8 
Tobacco 2.8  2.8 
Textiles, Apparel & Luxury Goods 2.7  2.8 
Leisure Equipment & Products 2.4  2.4 
Software 2.4  2.2 
Computers & Peripherals 2.2  2.8 
Specialty Retail 2.0  2.0 
Communications Equipment 1.7  2.1 
Media 1.7  1.7 
Aerospace & Defense 1.6  1.6 
Food Products 1.5  1.6 
Diversified Financial Services 1.4  1.4 
Food & Staples Retailing 1.4  1.6 
Oil, Gas & Consumable Fuels 1.4  — 
Chemicals 1.3  1.3 
Hotels, Restaurants & Leisure 1.3  1.3 
Internet & Catalog Retail 1.1  1.1 
Health Care Equipment & Supplies 0.9  1.1 
Building Products 0.4  1.5 
Other (1) 6.5  6.5 
100.0  % 100.0  %
___________________________
(1)Includes various industries with each industry individually less than 1.0% of the total combined LMM, Private Loan and Middle Market portfolio investments at each date.
Fair Value: March 31, 2025 December 31, 2024
Machinery 10.8  % 11.0  %
Diversified Consumer Services 5.9  6.0 
Internet Software & Services 5.3  5.9 
Health Care Providers & Services 5.2  4.5 
Professional Services 5.2  5.2 
Commercial Services & Supplies 4.8  4.8 
Electrical Equipment 4.8  3.7 
Distributors 4.4  4.2 
Construction & Engineering 4.1  4.3 
Computers & Peripherals 4.0  4.6 
Containers & Packaging 3.9  3.8 
Auto Components 3.7  3.6 
IT Services 3.5  3.7 
Energy Equipment & Services 2.9  2.9 
Tobacco 2.8  2.9 
Specialty Retail 2.5  2.5 
Software 2.4  2.3 
Textiles, Apparel & Luxury Goods 1.9  1.9 
Leisure Equipment & Products 1.7  1.7 
Media 1.7  1.9 
Aerospace & Defense 1.5  1.6 
Communications Equipment 1.5  1.4 
Food Products 1.4  1.5 
Diversified Financial Services 1.3  1.3 
Chemicals 1.2  1.2 
Food & Staples Retailing 1.2  1.2 
Oil, Gas & Consumable Fuels 1.2  — 
Internet & Catalog Retail 0.9  1.0 
Building Products 0.4  1.4 
Other (1) 7.9  8.0 
100.0  % 100.0  %
___________________________
(1)Includes various industries with each industry individually less than 1.0% of the total combined LMM, Private Loan and Middle Market portfolio investments at each date.