| Cash, Cash Equivalent, and Marketable Security |
5. Marketable Securities Investments in marketable securities, including those classified in cash and cash equivalents, are summarized as follows (in thousands): | | | | | | | | | | | | | | | | | | | | | | | | | As of June 30, 2026 | | Amortized Cost | | Unrealized Gains | | Unrealized Losses | | Fair Value | | U.S. Treasury securities | $ | 142,301 | | | $ | 7 | | | $ | (100) | | | $ | 142,208 | | | Corporate bonds | 74,170 | | | 12 | | | (83) | | | 74,099 | | | Commercial paper | 916 | | | — | | | — | | | 916 | | | Marketable equity securities | — | | | — | | | — | | | 19,718 | | | Total cash equivalents and marketable securities | 217,387 | | | 19 | | | (183) | | | 236,941 | | | Less: cash equivalents | (19,315) | | | — | | | 2 | | | (19,313) | | | Marketable securities | $ | 198,072 | | | $ | 19 | | | $ | (181) | | | $ | 217,628 | |
| | | | | | | | | | | | | | | | | | | | | | | | | As of December 31, 2025 | | Amortized Cost | | Unrealized Gains | | Unrealized Losses | | Fair Value | | U.S. Treasury securities | $ | 117,919 | | | $ | 171 | | | $ | (52) | | | $ | 118,038 | | | Corporate bonds | 114,640 | | | 147 | | | (121) | | | 114,666 | | | Commercial paper | 4,079 | | | — | | | (19) | | | 4,060 | | | Marketable equity securities | — | | | — | | | — | | | 18,654 | | | Total marketable securities | 236,638 | | | 318 | | | (192) | | | 255,418 | | | Less: cash equivalents | — | | | — | | | — | | | — | | | Marketable securities | $ | 236,638 | | | $ | 318 | | | $ | (192) | | | $ | 255,418 | |
The amortized cost and estimated fair value of marketable debt securities at June 30, 2026, including $19.3 million classified in cash and cash equivalents, are summarized below by contractual maturity dates (in thousands):
| | | | | | | | | | | | | Amortized cost | | Fair value | | Due within one year | $ | 169,607 | | | $ | 169,553 | | | Due after one year through five years | 47,777 | | | 47,670 | |
|