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Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2022
Accounting Policies [Abstract] |
Summary of Fair Value Measurement Financial Assets | Financial assets measured at fair value on a recurring basis were as follows (in thousands):
| Fair Value Measurement at December 31, 2022
| Total |  | Level 1 |  | Level 2
Assets: |  |  |  |  |
Money market funds | $ | 41,564 |  |  | $ | 41,564 |  |  | $ | — |
Government-sponsored enterprises | 32,811 |  |  | — |  |  | 32,811 |
Corporate debt securities | 17,626 |  |  | — |  |  | 17,626 |
Total assets measured at fair value (a) | $ | 92,001 |  |  | $ | 41,564 |  |  | $ | 50,437 |
| Fair Value Measurement at December 31, 2021
| Total |  | Level 1 |  | Level 2
Assets: |  |  |  |  |
Money market funds | $ | 17,202 |  |  | $ | 17,202 |  |  | $ | — |
U.S Treasury securities | 81,132 |  |  | 81,132 |  |  | — |
Government-sponsored enterprise | 7,734 |  |  | — |  |  | 7,734 |
Corporate debt securities | 37,280 |  |  | — |  |  | 37,280 |
Total assets measured at fair value (b) | $ | 143,348 |  |  | $ | 98,334 |  |  | $ | 45,014 |
(a) Total assets measured at fair value at December 31, 2022 includes approximately $46.5 million reported as cash and cash equivalents and $45.5 million reported as marketable securities on the balance sheet. (b) Total assets measured at fair value at December 31, 2021 includes approximately $23.2 million reported as cash and cash equivalents and $120.1 million reported as marketable securities on the balance sheet.
Summary of Percentage of Customer Concentration | The following table includes those counterparties that represent more than 10% of total revenue earned in the periods indicated:
| Year Ended December 31,
| 2022 |  | 2021 |  | 2020
Incyte Corporation (Incyte) | 26% |  | 31% |  | 47%
Janssen Biotech, Inc. (Janssen) | * |  | * |  | 19%
Zai Lab Limited (Zai Lab) | 15% |  | 30% |  | 11%
Provention Bio, Inc (Provention) | 43% |  | * |  | *
I-Mab Biopharma (I-Mab) | * |  | 16% |  | *
* Amount is less than 10% for the period indicated. The following table includes those counterparties that represent more than 10% of accounts receivable at the date indicated:
| December 31,
| 2022 |  | 2021
Provention | 84% |  | *
Zai Lab | * |  | 23%
I-Mab | * |  | 12%
McKesson Plasma & Biologics and McKesson Specialty Care Distribution LLC | * |  | 18%
ASD Healthcare and Oncology Supply | * |  | 18%
* Balance is less than 10% as of the date indicated.
Estimated Useful Lives | Depreciation and amortization are computed using the straight-line method over the following estimated useful lives:
Computer equipment | 3 years
Software | 3 years
Furniture | 10 years
Laboratory and office equipment | 5 years
Leasehold improvements | Shorter of lease term or useful life
Schedule of Stock Options and RSUs Excluded from the Calculation of Net Loss Per Share | The following table presents the number of stock options and RSUs that were excluded from the calculation of net loss per share:
| Year Ended December 31,
| 2022 |  | 2021 |  | 2020
Stock options and RSUs | 10,514,013 |  | 8,395,421 |  | 7,467,603

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