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Investment Transactions (Details) $ / shares in Units, $ in Thousands |  |  |  |  | 9 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 24, 2025 USD ($) installment shares | Aug. 04, 2025 USD ($) $ / shares | Feb. 24, 2025 USD ($) | May 29, 2024 USD ($) $ / shares shares | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($) | May 24, 2024
Asset Acquisition |  |  |  |  |  |  |  |
Cash paid for InvIOs investment |  |  |  |  | $ 0 | $ 4,196 |  |
Cash paid for Palvella notes receivable |  |  |  |  | 0 | $ 2,500 |  |
Net carrying value |  |  |  |  | 218,748 |  | $ 195,049 |
Agenus Bot/Bal |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Securities called by warrants (in shares) | shares |  |  |  | 867,052 |  |  |  |
Warrants term (in years) |  |  |  | 5 years |  |  |  |
Net carrying value |  |  |  | $ 75,000 |  |  |  |
Royalties right to receive (as a percent) |  |  |  | 18.75% |  |  |  |
Maximum capital sourcing |  |  |  | $ 100,000 |  |  |  |
Maximum financing royalty asset |  |  |  | $ 200,000 |  |  |  |
Exercise price (in USD per share) | $ / shares |  |  |  | $ 17.3 |  |  |  |
Agenus Bot/Bal | BMS-986442 |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Future milestones right to receive (as a percent) |  |  |  | 31.875% |  |  |  |
Agenus Bot/Bal | AGEN2373 |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Future milestones right to receive (as a percent) |  |  |  | 31.875% |  |  |  |
Agenus Bot/Bal | INCAGN2385 |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Future milestones right to receive (as a percent) |  |  |  | 31.875% |  |  |  |
Agenus Bot/Bal | INCAGN2390 |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Future milestones right to receive (as a percent) |  |  |  | 31.875% |  |  |  |
Agenus Bot/Bal | MK-4830 |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Future milestones right to receive (as a percent) |  |  |  | 31.875% |  |  |  |
Agenus Bot/Bal | UGN-301 |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Future milestones right to receive (as a percent) |  |  |  | 31.875% |  |  |  |
Agenus Bot/Bal | BOT/BAL |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Future royalties (as a percent) |  |  |  | 2.625% |  |  |  |
Agenus Partnered Program |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Additional maximum investment |  |  |  | $ 25,000 |  |  |  |
Castle Creek Investment |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Payments for repurchase of warrants |  |  |  |  | 5,800 |  |  |
Recognized research and development expense |  |  |  |  | 44,300 |  |  |
Payments to acquire productive assets |  |  | $ 50,000 |  | 50,100 |  |  |
Receivable with imputed interest, face amount |  |  | 8,300 |  |  |  |  |
Cash paid for Palvella notes receivable |  |  | 1,800 |  |  |  |  |
Castle Creek Investment | Purchasers |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Payments to acquire productive assets |  |  | 75,000 |  |  |  |  |
Castle Creek Investment | Other Purchasers |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Payments to acquire productive assets |  |  | $ 25,000 |  |  |  |  |
Orchestra BioMed |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Cash paid for InvIOs investment |  | $ 5,000 |  |  |  |  |  |
Price per share | $ / shares |  | $ 2.75 |  |  |  |  |  |
Orchestra Warrant |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Payments for repurchase of warrants |  | $ 2,300 |  |  |  |  |  |
Recognized research and development expense |  |  |  |  | $ 17,800 |  |  |
Orchestra BioMed |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Committed capital |  | 25,000 |  |  |  |  |  |
Investment amount, at closing |  | 20,000 |  |  |  |  |  |
Investment amount, to be funded |  | 15,000 |  |  |  |  |  |
Contracted royalty revenue |  | $ 100,000 |  |  |  |  |  |
Option Volatility | Agenus Warrant |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) |  |  |  |  | 1.14 |  |  | 0.84
Option Volatility | Minimum |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) | 0.32 |  |  |  |  |  |  |
Option Volatility | Maximum |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) | 0.33 |  |  |  |  |  |  |
Risk Free Interest Rate | Agenus Warrant |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) |  |  |  |  | 0.036 |  |  | 0.047
Risk Free Interest Rate | Minimum |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) |  |  |  |  | 0.047 |  |  |
Risk Free Interest Rate | Maximum |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) | 0.048 |  |  |  |  |  |  |
Acecor Warrants |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Securities called by warrants (in shares) | shares | 1,002,739 |  |  |  |  |  |  |
Warrants term (in years) | 10 years |  |  |  |  |  |  |
Payments for repurchase of warrants | $ 500 |  |  |  |  |  |  |
Orchestra Warrants | Option Volatility | Minimum |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) | 0.73 |  |  |  |  |  |  |
Orchestra Warrants | Option Volatility | Maximum |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) | 0.72 |  |  |  |  |  |  |
Orchestra Warrants | Risk Free Interest Rate | Minimum |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) |  |  |  |  | 0.044 |  |  |
Orchestra Warrants | Risk Free Interest Rate | Maximum |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) |  |  |  |  | 0.042 |  |  |
Castle Creek Warrant | Option Volatility | Minimum |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) |  |  | 1.10 |  |  |  |  |
Castle Creek Warrant | Option Volatility | Maximum |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) |  |  | 1.10 |  |  |  |  |
Castle Creek Warrant | Risk Free Interest Rate | Minimum |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) |  |  | 0.042 |  |  |  |  |
Castle Creek Warrant | Risk Free Interest Rate | Maximum |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Warrant measurement input (as a percent) |  |  | 0.036 |  |  |  |  |
Arecor Limited |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Asset acquisition, consideration transferred | $ 7,000 |  |  |  |  |  |  |
Asset acquisition, deferred consideration payable | $ 1,000 |  |  |  |  |  |  |
Asset acquisition, deferred consideration, number of installments | installment | 2 |  |  |  |  |  |  |
Asset acquisition financial royalty assets | $ 800 |  |  |  |  |  |  |
Arecor Limited | (AT229) Financial Royalty |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Asset acquisition financial royalty assets | 1,900 |  |  |  |  |  |  |
Payment for contingent consideration liability, investing activities | 3,000 |  |  |  |  |  |  |
Arecor Limited | (AT220) Financial Royalty |  |  |  |  |  |  |  |
Asset Acquisition |  |  |  |  |  |  |  |
Asset acquisition financial royalty assets | $ 4,800 |  |  |  |  |  |  |

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