7.Cash, Cash Equivalents and Short-Term Investments

Cash, cash equivalents and short-term investments for the periods presented consist of the following (in thousands):

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Cash equivalents and short-term investments include the following securities with gross unrealized gains and losses (in thousands):

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We maintain a depository relationship with Silicon Valley Bank (SVB). On March 10, 2023, SVB was closed by the California Department of Financial Protection and Innovation, which appointed the Federal Deposit Insurance Corporation (FDIC) as receiver. On March 12, 2023, federal regulators announced that the FDIC would complete its resolution of SVB in a manner that fully protects all depositors. On March 27, 2023, First Citizens BancShares, Inc. (FCB) announced that it entered into an agreement with FDIC to purchase all of the asset and liabilities of SVB. Customers of SVB automatically become customers of FCB following the acquisition. To date and as of March 31, 2023, the amount of our cash held on deposit with SVB/FCB was not material with respect our total cash, cash equivalents and short-term investments. All of our cash deposits with SVB/FCB are accessible to us, and we do not anticipate any losses with respect to such funds.

As of March 31, 2023 and December 31, 2022, our cash equivalents and short-term investments had a weighted-average time to maturity of approximately 58 days and 89 days, respectively. Our short-term investments are classified as available-for-sale securities. Accordingly, we have classified certain securities as short-term investments on our condensed balance sheets as they are available for use in the current operations. As of March 31, 2023, we had no investments that had been in a continuous unrealized loss position for more than 12 months. As of March 31, 2023, a total of 16 individual securities had been in an unrealized loss position for 12 months or less, and the losses were determined to be temporary. No significant facts or circumstances have arisen to indicate that there has been any significant deterioration in the creditworthiness of the issuers of the securities held by us. Based on our review of these securities, including the assessment of the duration and severity of the unrealized losses, we have not recognized any credit losses on these securities as of March 31, 2023 and December 31, 2022.

The following table shows the fair value and gross unrealized losses of our investments in individual securities that are in an unrealized loss position, aggregated by investment category (in thousands):

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