4.        Fair value of financial instruments and marketable securities

The Company follows the fair value measurement rules, which provideguidance on the use of fair value in accounting and disclosure for assets and liabilities when such accounting and disclosure is called for by other accounting literature. These rules establish a fair value hierarchy for inputs to be used to measure fair value of financial assets and liabilities. This hierarchy prioritizes the inputs to valuation techniques used to measure fair value into three levels: Level 1 (highest priority), Level 2, and Level 3 (lowest priority).

Cash equivalents and marketable securities are reflected in the accompanying financial statements at fair value. The carrying amount of receivables and accounts payable and accrued expenses approximates fair value due to the short-term nature of those instruments.

The Company’s marketable securities consist of both debt securities and equity investments. The Company previously owned common stock in ClearPoint Neuro, Inc. (“ClearPoint”) (formerly MRI Interventions, Inc.), a publicly traded medical device company. The ClearPoint equity investments (collectively, the “ClearPoint Equity Investments”) represented financial instruments, and therefore, were recorded at fair value, which was readily determinable. As of December 31, 2025, the Company sold all of its ClearPoint Equity Investments.

The Company has an investment in mutual funds that is denominated in a foreign currency and is classified as marketable securities on the Company’s consolidated balance sheets. This equity investment is reported at fair value, as it is readily available, and as such is classified as a Level 1 asset. Unrealized holding gains and losses for this equity investment are included as components of interest expense, net within the consolidated statement of operations.

The tables presented below are a summary of changes in the fair value for the Company’s marketable securities – equity investments and ClearPoint Equity Investments for the three and six months ended June 30, 2026 and June 30, 2025:

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Fair value of marketable securities that are classified as available for sale debt securities is based upon market prices using quoted prices in active markets for identical assets quoted on the last day of the period. In establishing the estimated fair value of the remaining available for sale debt securities, the Company used the fair value as determined by its investment advisors using observable inputs other than quoted prices.

The following represents the fair value using the hierarchy described above for the Company’s financial assets and liabilities that are required to be measured at fair value on a recurring basis as of June 30, 2026 and December 31, 2025:

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No transfers of assets between Level 1, Level 2, or Level 3 of the fair value measurement hierarchy occurred during the three and six months ended June 30, 2026 and year ended December 31, 2025.

The following is a summary of marketable securities accounted for as available for sale debt securities at June 30, 2026 and December 31, 2025:

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For available for sale debt securities in an unrealized loss position, the Company assesses whether it intends to sell or if it is more likely than not that the Company will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value. For the three and six months ended June 30, 2026 and 2025, no write downs occurred. The Company does not intend to sell the investments and it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost basis, which may be maturity. The Company also reviews its available for sale debt securities in an unrealized loss position and evaluates whether the decline in fair value has resulted from credit losses

or other factors. This review is subjective, as it requires management to evaluate whether an event or change in circumstances has occurred in that period that may be related to credit issues. For the three and six months ended June 30, 2026 and 2025, no allowance was recorded for credit losses. Unrealized gains and losses are reported as a component of accumulated other comprehensive income (loss) in stockholders’ deficit.

For the three and six months ended June 30, 2026 and 2025, realized gains from the sale of available for sale debt securities were immaterial. Realized gains and losses are reported as a component of interest expense, net in the consolidated statement of operations. Reclassified amounts from other comprehensive items were determined using the actual realized gains and losses from the sales of marketable securities.

The unrealized losses and fair values of available for sale debt securities that have been in an unrealized loss position for a period of less than and greater than or equal to 12 months as of June 30, 2026 are as follows:

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The unrealized losses and fair values of available for sale debt securities that have been in an unrealized loss position for a period of less than and greater than or equal to 12 months as of December 31, 2025 are as follows:

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Available for sale debt securities at June 30, 2026 and December 31, 2025 mature as follows:

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The Company classifies all of its marketable securities as current as they are all either available for sale debt securities or equity investments and are available for current operations.

Convertible senior notes

In June 2026, the Company issued, at par value, $550.0 million aggregate principal amount of 0% convertible senior notes due 2031 (the “2031 Convertible Notes”), which included an option to purchase up to an additional $50.0 million in aggregate principal amount of the 2031 Convertible Notes, which was exercised in full by the initial purchasers. The Company accounted for the 2031 Convertible Notes as a single liability measured at amortized cost, as further discussed in Note 9. The fair value of the 2031 Convertible Notes, which differs from their carrying values, is influenced by interest rates, the Company’s stock price and stock price volatility and is determined by prices for the 2031 Convertible Notes observed in market trading which are Level 2 inputs. The estimated fair value of the 2031 Convertible Notes at June 30, 2026 was $579.2 million.

In September 2019, the Company issued $287.5 million aggregate principal amount of 1.50% convertible senior notes due September 15, 2026 (the “2026 Convertible Notes”). In June 2026, the Company used a portion of the proceeds of the 2031 Convertible Notes to repurchase $222.0 million aggregate principal amount of its 2026 Convertible Notes for approximately $328.8 million, inclusive of accrued interest, as further discussed in Note 9. Additionally, during the three months ended June 30, 2026, a holder converted $10.0 million principal amount of the 2026 Convertible Notes in exchange for $12.9 million in cash and 3,506 shares of the Company’s common stock. Refer to Note 9 for further information. As of June 30, 2026, the remaining aggregate principal of the 2026 Convertible Notes is $55.5 million. The fair value of the 2026 Convertible Notes, which differs from their carrying values, is influenced by interest rates, the Company’s stock price and stock price volatility and is determined by prices for the 2026 Convertible Notes observed in market trading which are Level 2 inputs. The estimated fair value of the 2026 Convertible Notes at June 30, 2026 and December 31, 2025 was $85.5 million and $424.5 million, respectively.

Level 3 valuation

The contingent consideration payable is fair valued each reporting period with the change in fair value recorded as a gain or loss within the change in the fair value of contingent consideration on the consolidated statements of operations. In 2025, the probability of triggering the remaining contingent consideration was determined to be remote, and therefore the balance was written down to zero. Refer to Note 10 for additional details.