NOTE 3 — INVESTMENTS IN MARKETABLE DEBT SECURITIES

The estimated fair value of investments in marketable debt securities are classified as follows in the consolidated balance sheet as of June 30, 2023 (in thousands):

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The Company only invests in liquid, high quality debt securities. However, all of these investments are subject to interest rate and credit risk that may result in fluctuations in the fair value of the investments. To minimize the exposure due to an adverse shift in interest rates, the Company generally invests in securities with expected maturities of two years or less and maintains a weighted average maturity of one year or less. As of June 30, 2023 investments in marketable debt securities with a fair value of $85.9 million are scheduled to mature during the 12-month period ending June 30, 2024 and substantially all of the remaining investments with a fair value of $16.5 million, are scheduled to mature during the 12-month period ending June 30, 2025.

During the fiscal year ended June 30, 2023, no securities classified as available-for-sale were sold and the only redemptions occurred were as a result of the maturity of the respective investments. During the fiscal year ended June 30, 2022, the Company did not have any investments in marketable debt securities.

Accrued interest receivable on all marketable debt securities amounted to $0.3 million which is included in other current assets in the accompanying consolidated balance sheet as of June 30, 2023.  

The following table summarizes the unrealized gains and losses that result in differences between the amortized cost basis and fair value of the Company’s marketable debt securities held as of June 30, 2023 (in thousands):

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