Quarterly report pursuant to Section 13 or 15(d)

FAIR VALUE HIERARCHY FOR INVESTMENTS???PORTFOLIO COMPOSITION

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FAIR VALUE HIERARCHY FOR INVESTMENTS—PORTFOLIO COMPOSITION
3 Months Ended
Mar. 31, 2024
Fair Value Disclosures [Abstract]  
FAIR VALUE HIERARCHY FOR INVESTMENTS—PORTFOLIO COMPOSITION FAIR VALUE HIERARCHY FOR INVESTMENTS—PORTFOLIO COMPOSITION
ASC 820 defines fair value, establishes a framework for measuring fair value, establishes a fair value hierarchy based on the quality of inputs used to measure fair value, and enhances disclosure requirements for fair value measurements. Main Street accounts for its investments at fair value.
Fair Value Hierarchy
In accordance with ASC 820, Main Street has categorized its investments based on the priority of the inputs to the valuation technique into a three-level fair value hierarchy. The fair value hierarchy gives the highest priority to quoted prices in active markets for identical investments (Level 1) and the lowest priority to unobservable inputs (Level 3).
Investments recorded on Main Street’s Consolidated Balance Sheets are categorized based on the inputs to the valuation techniques as follows:
Level 1—Investments whose values are based on unadjusted quoted prices for identical assets in an active market that Main Street has the ability to access (examples include investments in active exchange-traded equity securities and investments in most U.S. government and agency securities).
Level 2—Investments whose values are based on quoted prices in markets that are not active or model inputs that are observable either directly or indirectly for substantially the full term of the investment. Level 2 inputs include the following:
Quoted prices for similar assets in active markets (for example, investments in restricted stock);
Quoted prices for identical or similar assets in non-active markets (for example, investments in thinly traded public companies);
Pricing models whose inputs are observable for substantially the full term of the investment (for example, market interest rate indices); and
Pricing models whose inputs are derived principally from, or corroborated by, observable market data through correlation or other means for substantially the full term of the investment.
Level 3—Investments whose values are based on prices or valuation techniques that require inputs that are both unobservable and significant to the overall fair value measurement (for example, investments in illiquid securities issued by privately held companies). These inputs reflect management’s own assumptions about the assumptions a market participant would use in pricing the investment.
As required by ASC 820, when the inputs used to measure fair value fall within different levels of the hierarchy, the level within which the fair value measurement is categorized is based on the lowest level input that is significant to the fair value measurement in its entirety. For example, a Level 3 fair value measurement may include inputs that are observable (Levels 1 and 2) and unobservable (Level 3). Therefore, unrealized appreciation and depreciation related to such investments categorized within the Level 3 tables below may include changes in fair value that are attributable to both observable inputs (Levels 1 and 2) and unobservable inputs (Level 3).
As of March 31, 2024 and December 31, 2023, all of Main Street’s LMM portfolio investments consisted of illiquid securities issued by privately held companies and the fair value determination for these investments primarily
consisted of unobservable inputs. As a result, all of Main Street’s LMM portfolio investments were categorized as Level 3 as of March 31, 2024 and December 31, 2023.
As of March 31, 2024 and December 31, 2023, Main Street’s Private Loan portfolio investments primarily consisted of investments in secured debt investments. The fair value determination for these investments consisted of a combination of observable inputs in non-active markets for which sufficient observable inputs were not available to determine the fair value of these investments and unobservable inputs. As a result, all of Main Street’s Private Loan portfolio investments were categorized as Level 3 as of March 31, 2024 and December 31, 2023.
As of March 31, 2024 and December 31, 2023, Main Street’s Middle Market portfolio investments consisted primarily of investments in secured and unsecured debt investments and independently rated debt investments. The fair value determination for these investments consisted of a combination of observable inputs in non-active markets for which sufficient observable inputs were not available to determine the fair value of these investments and unobservable inputs. As a result, all of Main Street’s Middle Market portfolio investments were categorized as Level 3 as of March 31, 2024 and December 31, 2023.
As of March 31, 2024 and December 31, 2023, Main Street’s Other Portfolio investments consisted of illiquid securities issued by privately held entities and the fair value determination for these investments primarily consisted of unobservable inputs. As a result, all of Main Street’s Other Portfolio investments were categorized as Level 3 as of March 31, 2024 and December 31, 2023.
As of March 31, 2024, Main Street held several short-term portfolio investments consisting primarily of secured debt investments. The fair value determination for these investments consisted of available observable inputs in non-active markets sufficient to determine the fair value of the investments. As a result, Main Street’s short-term portfolio investments were categorized as Level 2 as of March 31, 2024. As of December 31, 2023, Main Street did not hold any short-term portfolio investments.

As of March 31, 2024 and December 31, 2023, all money market funds included in cash and cash equivalents were valued using Level 1 inputs.
The fair value determination of each portfolio investment categorized as Level 3 required one or more of the following unobservable inputs:
Financial information obtained from each portfolio company, including unaudited statements of operations and balance sheets for the most recent period available as compared to budgeted numbers;
Current and projected financial condition of the portfolio company;
Current and projected ability of the portfolio company to service its debt obligations;
Type and amount of collateral, if any, underlying the investment;
Current financial ratios (e.g., fixed charge coverage ratio, interest coverage ratio and net debt/EBITDA ratio) applicable to the investment;
Current liquidity of the investment and related financial ratios (e.g., current ratio and quick ratio);
Pending debt or capital restructuring of the portfolio company;
Projected operating results of the portfolio company;
Current information regarding any offers to purchase the investment;
Current ability of the portfolio company to raise any additional financing as needed;
Changes in the economic environment which may have a material impact on the operating results of the portfolio company;
Internal occurrences that may have an impact (both positive and negative) on the operating performance of the portfolio company;
Qualitative assessment of key management;
Contractual rights, obligations or restrictions associated with the investment; and
Other factors deemed relevant.
The use of significant unobservable inputs creates uncertainty in the measurement of fair value as of the reporting date. The significant unobservable inputs used in the fair value measurement of Main Street’s LMM equity securities, which are generally valued through an average of the discounted cash flow technique and the market comparable/enterprise value technique (unless one of these approaches is determined to not be appropriate), are (i) EBITDA multiples and (ii) the weighted-average cost of capital (“WACC”). Significant increases (decreases) in EBITDA multiple inputs in isolation would result in a significantly higher (lower) fair value measurement. On the contrary, significant increases (decreases) in WACC inputs in isolation would result in a significantly lower (higher) fair value measurement. The significant unobservable inputs used in the fair value measurement of Main Street’s LMM, Private Loan and Middle Market securities are (i) risk adjusted discount rates used in the Yield-to-Maturity valuation technique (see Note B.1. — Summary of Significant Accounting Policies — Valuation of the Investment Portfolio) and (ii) the percentage of expected principal recovery. Significant increases (decreases) in any of these discount rates in isolation would result in a significantly lower (higher) fair value measurement. Significant increases (decreases) in any of these expected principal recovery percentages in isolation would result in a significantly higher (lower) fair value measurement. However, due to the nature of certain investments, fair value measurements may be based on other criteria, such as third-party appraisals of collateral and fair values as determined by independent third parties, which are not presented in the tables below.
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, 2024 and December 31, 2023:
Type of
Investment
Fair Value as of
March 31, 2024
(in thousands)
Valuation Technique Significant Unobservable Inputs Range (4) Weighted Average (4) Median (4)
Equity investments $ 1,447,635  Discounted cash flow WACC
9.3% - 22.4%
14.3  % 15.1  %
Market comparable / Enterprise value EBITDA multiple (1) (3)
4.5x - 8.9x (2)
7.1x 6.3x
Debt investments $ 2,808,138  Discounted cash flow Risk adjusted discount factor (5)
9.4% - 18.4% (2)
12.9  % 12.7  %
Expected principal recovery percentage
0.0% - 100.0%
99.4  % 100.0  %
Debt investments $ 188,871  Market approach Third-party quote
38.3 - 100.5
90.9 95.9
Total Level 3 investments $ 4,444,644 
____________________
(1)EBITDA may include proforma adjustments and/or other addbacks 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 - 15.7x and the range for risk adjusted discount factor is 5.0% - 31.9%.
(3)The fair value of the equity investment in the External Investment Manager is based on a fee multiple of 7.5x. 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)Discount rate includes the effect of the standard SOFR base rate, as applicable.
Type of Investment
Fair Value as of December 31, 2023
(in thousands)
Valuation Technique Significant Unobservable Inputs Range (4) Weighted Average (4) Median (4)
Equity investments $ 1,402,354  Discounted cash flow WACC
9.7% - 22.7%
14.5  % 15.5  %
Market comparable / Enterprise value EBITDA multiple (1) (3)
4.8x - 8.9x (2)
7.1x 6.4x
Debt investments $ 2,720,425  Discounted cash flow Risk adjusted discount factor (5)
9.8% - 18.0% (2)
12.9  % 13.0  %
Expected principal recovery percentage
0.0% - 100.0%
99.7  % 100.0  %
Debt investments $ 163,492  Market approach Third-party quote
3.0 - 100.0
89.8 92.4
Total Level 3 investments $ 4,286,271 
____________________
(1)EBITDA may include proforma adjustments and/or other addbacks 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 - 15.7x and the range for risk adjusted discount factor is 7.0% - 31.6%.
(3)The fair value of the equity investment in the External Investment Manager is based on a fee multiple of 7.2x. 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)Discount rate includes the effect of the standard SOFR base rate, as applicable.
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, 2024 and 2023 (amounts in thousands):
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.
Type of Investment
Fair Value
as of
December 31, 2022
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, 2023
Debt $ 2,928,196  $ —  $ (88,300) $ 106,658  $ 33,064  $ (26,440) $ (11,446) $ 2,941,732 
Equity 1,166,643  —  (2,871) 8,476  (3,946) 29,890  14,022  1,212,214 
Equity Warrant 5,434  —  —  —  —  2,171  (2,576) 5,029 
$ 4,100,273  $ —  $ (91,171) $ 115,134  $ 29,118  $ 5,621  $ —  $ 4,158,975 
____________________
(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.
At March 31, 2024 and December 31, 2023, 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)
At March 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 $ 2,361,511  $ —  $ —  $ 2,361,511 
Private Loan portfolio investments 1,519,538  —  —  1,519,538 
Middle Market portfolio investments 238,553  —  —  238,553 
Other Portfolio investments 139,782  —  —  139,782 
External Investment Manager 185,260  —  —  185,260 
Short-term portfolio investments 103,383  —  103,383  — 
Total investments $ 4,548,027  $ —  $ 103,383  $ 4,444,644 
Fair Value Measurements
(in thousands)
At December 31, 2023
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 $ 2,273,000  $ —  $ —  $ 2,273,000 
Private Loan portfolio investments 1,453,549  —  —  1,453,549 
Middle Market portfolio investments 243,695  —  —  243,695 
Other Portfolio investments 141,964  —  —  141,964 
External Investment Manager 174,063  —  —  174,063 
Total investments $ 4,286,271  $ —  $ —  $ 4,286,271 
Investment Portfolio Composition
Main Street’s principal investment objective is to maximize its portfolio’s total return by generating current income from its debt investments and current income and capital appreciation from its equity and equity-related investments, including warrants, convertible securities and other rights to acquire equity securities in a portfolio company. Main Street seeks to achieve its investment objective primarily through its LMM and Private Loan investment strategies.
Main Street’s LMM investment strategy is focused on investments in secured debt and equity in privately held, LMM companies based in the United States. Main Street’s LMM portfolio companies generally have annual revenues between $10 million and $150 million, and its LMM investments generally range in size from $5 million to $100 million. The LMM debt investments are typically secured by a first priority lien on the assets of the portfolio company, can include either fixed or floating rate terms and generally have a term of between five and seven years from the original investment date. In most LMM portfolio investments, Main Street makes direct equity investments and/or receives nominally priced equity warrants in connection with a debt investment.
Main Street’s private loan (“Private Loan”) investment strategy is focused on investments in privately held companies that are generally consistent with the size of its LMM portfolio companies or Middle Market portfolio companies, and its Private Loan investments generally range in size from $10 million to $75 million. Main Street’s Private Loan investments primarily consist of debt securities that have primarily been originated directly by Main Street or, to a lesser extent, through its strategic relationships with other investment funds on a collaborative basis through investments that are often referred to in the debt markets as “club deals” because of the small lender group size. In both cases, our Private Loan investments are typically made to support a company owned by or in the process of being acquired by a
private equity sponsor. Main Street’s Private Loan portfolio debt investments are generally secured by a first priority lien on the assets of the portfolio company and typically have a term of between three and seven years from the original investment date. Main Street may have the option to co-invest with the sponsor in the equity securities of its Private Loan portfolio companies.
Main Street has also historically maintained a Middle Market investment strategy which is focused on investments in syndicated loans to or debt securities in Middle Market companies, which Main Street defines as companies with annual revenues between $150 million and $1.5 billion, and its Middle Market investments generally range in size from $3 million to $25 million. Main Street’s Middle Market portfolio debt investments are generally secured by a first priority lien on the assets of the portfolio company and typically have an expected duration of between three and seven years from the original investment date. Over the last few years, Main Street has been de-emphasizing this strategy and expects to continue to do so in the future.
Main Street’s other portfolio (“Other Portfolio”) investments primarily consist of investments that are not consistent with the typical profiles for its LMM, Private Loan or Middle Market portfolio investments, including investments which may be managed by third parties. In the Other Portfolio, Main Street may incur indirect fees and expenses in connection with investments managed by third parties, such as investments in other investment companies or private funds. For Other Portfolio investments, Main Street generally receives distributions related to the assets held by the portfolio company. Those assets are typically expected to be liquidated over a five to ten-year period.
Based upon Main Street’s liquidity and capital structure management activities, Main Street’s Investment Portfolio may also include short-term portfolio investments that are atypical of Main Street’s LMM, Private Loan and Middle Market portfolio investments in that they are intended to be a short-term deployment of capital. Those assets are typically expected to be liquidated in one year or less. These short-term portfolio investments are not expected to be a significant portion of the overall Investment Portfolio.
Main Street’s external asset management business is conducted through its External Investment Manager. The External Investment Manager earns management fees based on the assets under management for External Parties and may earn incentive fees, or a carried interest, based on the performance of the assets managed. Main Street entered into an agreement with the External Investment Manager to share employees in connection with its asset management business generally, and specifically for its relationship with MSC Income Fund, Inc. (“MSC Income”) and its other clients. Through this agreement, Main Street shares employees with the External Investment Manager, including their related infrastructure, business relationships, management expertise and capital raising capabilities. Main Street allocates the related expenses to the External Investment Manager pursuant to the sharing agreement. Main Street’s total expenses for the three months ended March 31, 2024 and 2023 are net of expenses allocated to the External Investment Manager of $5.6 million and $5.0 million, respectively.
Investment income, consisting of interest, dividends and fees, can fluctuate dramatically due to various factors, including the level of new investment activity, repayments of debt investments or sales of equity interests. Investment income in any given year could also be highly concentrated among several portfolio companies. For the three months ended March 31, 2024 and 2023, Main Street did not record investment income from any single portfolio company in excess of 10% of total investment income.
The following tables provide a summary of Main Street’s investments in the LMM, Private Loan and Middle Market portfolios as of March 31, 2024 and December 31, 2023 (this information excludes Other Portfolio investments, short-term portfolio investments and the External Investment Manager, which are discussed further below).
As of March 31, 2024
LMM (a) Private Loan Middle Market
(dollars in millions)
Number of portfolio companies 81  88  22 
Fair value $ 2,361.5  $ 1,519.5  $ 238.6 
Cost $ 1,850.3  $ 1,538.3  $ 284.8 
Debt investments as a % of portfolio (at cost) 72.5  % 94.7  % 91.0  %
Equity investments as a % of portfolio (at cost) 27.5  % 5.3  % 9.0  %
% of debt investments at cost secured by first priority lien 99.2  % 99.9  % 99.0  %
Weighted-average annual effective yield (b) 12.8  % 12.8  % 12.9  %
Average EBITDA (c) $ 8.7  $ 32.8  $ 61.1 
____________________
(a)At March 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 40%.
(b)The weighted-average annual effective yields were computed using the effective interest rates for all debt investments at cost as of March 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. The weighted-average annual effective yield on Main Street’s debt portfolio as of March 31, 2024 including debt investments on non-accrual status was 12.7% for its LMM portfolio, 12.4% for its Private Loan portfolio and 11.4% for its Middle Market 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 and Middle Market portfolios. These calculations exclude certain portfolio companies, including four LMM portfolio companies, two Private Loan portfolio companies and one Middle Market portfolio company, 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.
As of December 31, 2023
LMM (a) Private Loan Middle Market
(dollars in millions)
Number of portfolio companies 80  87  23 
Fair value $ 2,273.0  $ 1,453.5  $ 243.7 
Cost $ 1,782.9  $ 1,470.1  $ 294.4 
Debt investments as a % of portfolio (at cost) 72.0  % 94.7  % 91.4  %
Equity investments as a % of portfolio (at cost) 28.0  % 5.3  % 8.6  %
% of debt investments at cost secured by first priority lien 99.2  % 100.0  % 99.1  %
Weighted-average annual effective yield (b) 13.0  % 12.9  % 12.5  %
Average EBITDA (c) $ 8.2  $ 27.2  $ 64.2 
____________________
(a)At December 31, 2023, Main Street had equity ownership in all of its LMM portfolio companies, and the average fully diluted equity ownership in those portfolio companies was 40%.
(b)The weighted-average annual effective yields were computed using the effective interest rates for all debt investments at cost as of December 31, 2023, 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. The weighted-average annual effective yield on Main Street’s debt portfolio as of December 31, 2023 including debt investments on non-accrual status was 12.9% for its LMM portfolio, 12.5% for its Private Loan portfolio and 10.8% for its Middle Market 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 and Middle Market portfolios. These calculations exclude certain portfolio companies, including two LMM portfolio companies and two 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.
For the three months ended March 31, 2024 and 2023, Main Street achieved an annualized total return on investments of 16.7% and 13.4%, respectively. For the year ended December 31, 2023, Main Street achieved a total return on investments of 16.3%. Total return on investments is calculated using the interest, dividend and fee income, as well as the realized and unrealized change in fair value of the Investment Portfolio for the specified period. Main Street’s total return on investments 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.
As of March 31, 2024, Main Street had Other Portfolio investments in 14 entities, collectively totaling $139.8 million in fair value and $141.2 million in cost basis and which comprised 3.1% and 3.6% of Main Street’s Investment Portfolio at fair value and cost, respectively. As of December 31, 2023, Main Street had Other Portfolio investments in 15 entities, collectively totaling $142.0 million in fair value and $149.1 million in cost basis and which comprised 3.3% and 4.0% of Main Street’s Investment Portfolio at fair value and cost, respectively.
As of March 31, 2024, Main Street had short-term portfolio investments in 11 entities, collectively totaling $103.4 million in fair value and $103.3 million in cost basis and which comprised 2.3% and 2.6% of Main Street’s Investment Portfolio at fair value and cost, respectively. As of December 31, 2023, Main Street held no short-term portfolio investments.
As discussed further in Note A.1. — Organization and Basis of Presentation — Organization, Main Street holds an investment in the External Investment Manager, a wholly-owned subsidiary that is treated as a portfolio investment. As of March 31, 2024, this investment had a fair value of $185.3 million and a cost basis of $29.5 million, which comprised 4.1% and 0.7% of Main Street’s Investment Portfolio at fair value and cost, respectively. As of December 31, 2023, this investment had a fair value of $174.1 million and a cost basis of $29.5 million, which comprised 4.1% and 0.8% of Main Street’s Investment Portfolio at fair value and cost, respectively.
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, 2024 and December 31, 2023 (this information
excludes Other Portfolio investments, short-term portfolio investments and the External Investment Manager, which are discussed above).
Cost: March 31, 2024 December 31, 2023
First lien debt 83.0  % 82.7  %
Equity 16.5  16.8 
Second lien debt 0.1  0.1 
Equity warrants 0.2  0.2 
Other 0.2  0.2 
100.0  % 100.0  %
Fair Value: March 31, 2024 December 31, 2023
First lien debt 71.6  % 71.6  %
Equity 27.8  27.8 
Second lien debt 0.2  0.2 
Equity warrants 0.2  0.2 
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, 2024 and December 31, 2023 (this information excludes Other Portfolio investments, short-term 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, 2024 December 31, 2023
West 26.7  % 25.8  %
Northeast 21.4  22.3 
Southwest 19.5  19.7 
Midwest 16.8  17.0 
Southeast 13.7  13.1 
Canada 0.4  0.4 
Other Non-United States 1.5  1.7 
100.0  % 100.0  %
Fair Value: March 31, 2024 December 31, 2023
West 26.0  % 25.4  %
Southwest 21.9  22.0 
Northeast 20.5  21.3 
Midwest 18.0  18.1 
Southeast 11.8  11.3 
Canada 0.4  0.3 
Other Non-United States 1.4  1.6 
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, 2024 and December 31, 2023 (this information excludes Other Portfolio investments, short-term portfolio investments and the External Investment Manager).
Cost: March 31, 2024 December 31, 2023
Internet Software & Services 7.4  % 7.6  %
Machinery 7.4  7.7 
Professional Services 5.9  6.0 
IT Services 5.1  5.0 
Construction & Engineering 5.0  4.9 
Diversified Consumer Services 4.8  4.9 
Commercial Services & Supplies 4.6  4.5 
Health Care Providers & Services 4.6  5.4 
Distributors 4.1  4.3 
Containers & Packaging 3.7  3.8 
Energy Equipment & Services 3.4  2.7 
Tobacco 3.2  3.1 
Leisure Equipment & Products 3.1  3.1 
Textiles, Apparel & Luxury Goods 3.1  3.2 
Electrical Equipment 3.0  1.6 
Aerospace & Defense 2.7  2.9 
Computers & Peripherals 2.5  2.7 
Specialty Retail 2.5  2.1 
Media 2.2  2.4 
Software 2.2  2.0 
Building Products 1.7  1.7 
Food Products 1.7  1.6 
Diversified Financial Services 1.6  1.7 
Food & Staples Retailing 1.6  1.6 
Auto Components 1.5  1.6 
Electronic Equipment, Instruments & Components 1.5  1.5 
Health Care Equipment & Supplies 1.3  1.3 
Internet & Catalog Retail 1.3  1.3 
Communications Equipment 1.2  1.2 
Hotels, Restaurants & Leisure 1.1  1.1 
Household Products 1.0  1.0 
Chemicals 0.9  1.0 
Other 3.1  3.5 
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, 2024 December 31, 2023
Machinery 8.6  % 8.8  %
Diversified Consumer Services 7.0  7.1 
Professional Services 6.4  6.5 
Internet Software & Services 6.0  6.2 
Construction & Engineering 5.2  5.1 
IT Services 4.7  4.6 
Computers & Peripherals 4.4  4.4 
Distributors 4.4  4.5 
Health Care Providers & Services 4.4  5.0 
Commercial Services & Supplies 3.9  3.9 
Containers & Packaging 3.8  3.9 
Tobacco 3.3  3.2 
Energy Equipment & Services 3.2  2.5 
Specialty Retail 3.0  2.7 
Electrical Equipment 2.8  1.7 
Aerospace & Defense 2.5  2.7 
Media 2.5  2.7 
Leisure Equipment & Products 2.4  2.5 
Textiles, Apparel & Luxury Goods 2.3  2.6 
Software 2.2  2.1 
Diversified Financial Services 1.6  1.6 
Food Products 1.6  1.5 
Building Products 1.5  1.5 
Auto Components 1.4  1.5 
Food & Staples Retailing 1.2  1.2 
Air Freight & Logistics 1.1  1.1 
Internet & Catalog Retail 1.1  1.2 
Construction Materials 1.0  1.0 
Health Care Equipment & Supplies 1.0  1.0 
Other 5.5  5.7 
100.0  % 100.0  %
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(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.
At March 31, 2024 and December 31, 2023, Main Street had no portfolio investment that was greater than 10% of the Investment Portfolio at fair value.
Unconsolidated Significant Subsidiaries
In accordance with Rules 3-09 and 4-08(g) of Regulation S-X, Main Street must determine which of its unconsolidated controlled portfolio companies, if any, are considered “significant subsidiaries.” In evaluating its unconsolidated controlled portfolio companies in accordance with Regulation S-X, there are two tests that Main Street must utilize to determine if any of Main Street’s Control Investments (as defined in Note A — Organization and Basis of Presentation, including those unconsolidated portfolio companies defined as Control Investments in which Main Street does not own greater than 50% of the voting securities nor have rights to maintain greater than 50% of the board
representation) are considered significant subsidiaries: the investment test and the income test. The investment test is generally measured by dividing Main Street’s investment in the Control Investment by the value of Main Street’s total investments. The income test is generally measured by dividing the absolute value of the combined sum of total investment income, net realized gain (loss) and net unrealized appreciation (depreciation) from the relevant Control Investment for the period being tested by the absolute value of Main Street’s change in net assets resulting from operations for the same period. Rules 3-09 and 4-08(g) of Regulation S-X require Main Street to include (1) separate audited financial statements of an unconsolidated majority-owned subsidiary (Control Investments in which Main Street owns greater than 50% of the voting securities) in an annual report and (2) summarized financial information of a Control Investment in a quarterly report, respectively, if certain thresholds of the investment or income tests are exceeded and the unconsolidated portfolio company qualifies as a significant subsidiary.
As of March 31, 2024 and December 31, 2023, Main Street had no single investment that qualified as a significant subsidiary under either the investment or income tests.