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CONSOLIDATED SCHEDULE OF INVESTMENTS (Parenthetical) $ in Thousands | Sep. 30, 2023 USD ($) | Dec. 31, 2022 USD ($) Firm
--- | --- | ---
Investment Holding [Line Items] |  |
Investment, basis spread, variable rate | 8.50% | 7.50%
Tax basis of investments, gross, unrealized appreciation | $ 97,200 | $ 72,200
Tax basis of investments, gross, unrealized depreciation | 143,100 | 112,000
Tax basis of investments, unrealized appreciation (depreciation), net | 45,900 | 39,800
Tax basis of investments, cost for income tax purposes | 3,300,000 | 3,000,000
Investment cost | 3,308,894 | 3,005,696
Investments, at fair value: | $ 3,261,391 | $ 2,963,955
1-month LIBOR |  |
Investment Holding [Line Items] |  |
Interest rate | 5.43% | 4.40%
3-month LIBOR |  |
Investment Holding [Line Items] |  |
Interest rate | 5.66% | 4.77%
6-month LIBOR |  |
Investment Holding [Line Items] |  |
Interest rate | 5.90% | 5.14%
1-month SOFR |  |
Investment Holding [Line Items] |  |
Interest rate | 5.32% |
3-month SOFR |  |
Investment Holding [Line Items] |  |
Interest rate | 5.27% |
6-month SOFR |  |
Investment Holding [Line Items] |  |
Interest rate | 5.17% |
Common Stock | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Investment Holding [Line Items] |  |
Number of publicly traded companies | Firm |  | 43
Warrants | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Investment Holding [Line Items] |  |
Number of publicly traded companies | Firm |  | 27
Phathom Pharmaceuticals, Inc. | Royalty Contract |  |
Investment Holding [Line Items] |  |
Investment cost | $ 4,600 | $ 4,600
Investments, at fair value: | 3,200 | 3,400
Black Crow AI, Inc. affiliates | Promissory Notes [Member] |  |
Investment Holding [Line Items] |  |
Principal amount | $ 2,400 | $ 3,000

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