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CONSOLIDATED SCHEDULE OF INVESTMENTS (Parenthetical) $ in Thousands | Dec. 31, 2023 USD ($) Firm | Dec. 31, 2022 USD ($) Firm
--- | --- | ---
Summary of Investment Holdings |  |
Investment, basis spread, variable rate | 8.50% |
Tax basis of investments, gross, unrealized appreciation | $ 118,300 | $ 72,200
Tax basis of investments, gross, unrealized depreciation | 115,900 | 112,000
Tax basis of investments, unrealized appreciation (depreciation), net | 2,400 | (39,800)
Tax basis of investments, cost for income tax purposes | 3,200,000 | 3,000,000
Investment cost | 3,247,033 | 3,005,696
Investments, at fair value: | 3,248,046 | 2,963,955
Black Crow AI, Inc. | Promissory Notes |  |
Summary of Investment Holdings |  |
Principal amount | 2,400 | 3,000
Phathom Pharmaceuticals, Inc. | Royalty Contract |  |
Summary of Investment Holdings |  |
Investment cost | 12,000 | 4,600
Investments, at fair value: | $ 9,400 | $ 3,400
Quoted Prices in Active Markets for Identical Assets (Level 1) | Warrants |  |
Summary of Investment Holdings |  |
Number of publicly traded companies | Firm | 24 | 27
Quoted Prices in Active Markets for Identical Assets (Level 1) | Common Stock |  |
Summary of Investment Holdings |  |
Number of publicly traded companies | Firm | 36 | 43
PRIME |  |
Summary of Investment Holdings |  |
Investment, basis spread, variable rate |  | 7.50%
1-month SOFR |  |
Summary of Investment Holdings |  |
Interest rate | 5.34% |
3-month SOFR |  |
Summary of Investment Holdings |  |
Interest rate | 5.36% |
6-month SOFR |  |
Summary of Investment Holdings |  |
Interest rate | 5.35% |
1-month LIBOR |  |
Summary of Investment Holdings |  |
Interest rate |  | 4.40%
3-month LIBOR |  |
Summary of Investment Holdings |  |
Interest rate |  | 4.77%
6-month LIBOR |  |
Summary of Investment Holdings |  |
Interest rate |  | 5.14%

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