4.    Stockholders’ Equity

Common Stock

During the six months ended June 30, 2025, the Company issued 309,535 shares of common stock as a result of stock option exercises, for gross proceeds of $403, issued 503,332 shares from the vesting of restricted stock units, and issued 68,179 shares to employees pursuant to the MaxCyte, Inc. 2021 Employee Stock Purchase Plan (the “ESPP”) for gross proceeds of $134.

Preferred Stock

The Company’s certificate of incorporation authorizes the issuance of up to 5,000,000 shares of preferred stock, par value $0.01 per share. As of June 30, 2025 and December 31, 2024, no shares of preferred stock were issued or outstanding.

Stock Incentive Plans

The Company adopted the MaxCyte, Inc. Long-Term Incentive Plan (the “2016 Plan”) in January 2016 to provide for the awarding of (i) stock options, (ii) restricted stock, (iii) incentive shares, and (iv) performance awards, in each case, to employees, officers, and directors of the Company and to other individuals as determined by the Board of Directors of the Company.

In December 2021, the Company adopted the MaxCyte, Inc. 2021 Inducement Plan (the “Inducement Plan”) to provide for the awarding of (i) non-qualified stock options; (ii) stock appreciation rights; (iii) restricted stock awards; (iv) restricted stock unit awards; (v) performance awards; and (vi) other awards, in each case, only to persons eligible to receive grants of awards who satisfy the standards for inducement grants under Nasdaq Marketplace Rule 5635(c)(4) or 5635(c)(3), if applicable, and the related guidance under Nasdaq IM 5635-1.

In May 2022, the Board of Directors adopted, and in June 2022, the Company’s stockholders approved, the MaxCyte, Inc. 2022 Equity Incentive Plan (the “2022 Plan”) to provide for the awarding of (i) incentive stock options, (ii) non-qualified stock options, (iii) stock appreciation rights, (iv) restricted stock awards, (v) restricted stock unit awards, (vi) performance awards, and (vii) other awards. Following the approval of the 2022 Plan, no additional awards can be granted under the 2016 Plan or the Inducement Plan, but all outstanding awards will continue to remain subject to the terms of the applicable plan.

Upon the effectiveness of the 2022 Plan, a total of 3,692,397 shares were initially reserved for issuance pursuant to future awards under the 2022 Plan, consisting of 1,928,000 new shares and 1,764,397 shares previously available under the 2016 Plan. If and to the extent that outstanding options under the 2016 Plan or the Inducement Plan are forfeited, the shares underlying such forfeited options will become available for issuance under the 2022 Plan. At the Company’s Annual Meeting of Stockholders held on June 22, 2023, the Company’s stockholders approved an increase by 6,069,000 in the maximum number of shares of common stock to be authorized under the 2022 Plan.  At the Company’s Annual Meeting of Stockholders held on June 11, 2024, the Company’s stockholders approved to increase by 2,300,000 the maximum

number of shares of common stock authorized to be issued under the 2022 Plan.  At the Company’s Annual Meeting of Stockholders held on June 18, 2025, the Company’s stockholders approved to increase by 2,950,000 the maximum number of shares of common stock authorized to be issued under the 2022 Plan.

At June 30, 2025 and December 31, 2024, there were 5,443,100 and 6,946,000 shares, respectively, available to be issued under the 2022 Plan.

The value of an equity award is recognized as expense on a straight-line basis over the requisite service period. At June 30, 2025, total unrecognized compensation expense was $19,494, which will be recognized over an estimated weighted-average period of 2.6 years.

Stock Options

The weighted-average fair value of the stock options granted during the three months ended June 30, 2025 and 2024 was estimated to be $1.17 and $2.45, per option share, respectively.  The weighted-average fair value of the stock options granted during the six months ended June 30, 2025 and 2024 was estimated to be $1.72 and $2.28, per option share, respectively.  

Restricted Stock Units (“RSUs”)

The weighted-average fair value of the RSUs granted during the three months ended June 30, 2025 and 2024 was estimated to be $2.16 and $4.69 per RSU, respectively.  The weighted-average fair value of the RSUs granted during the six months ended June 30, 2025 and 2024 was estimated to be $3.05 and $4.43 per RSU, respectively.

Performance Stock Units (“PSUs”)

During the six months ended June 30, 2025 and 2024, the Company awarded 554,938 and 550,838 PSUs, respectively, to certain members of management including executive officers.  The PSU awards represent a number of shares of common stock to be earned if a target level of performance, as approved by the Board of Directors, is achieved.  The performance period continues through December 31, 2027 for the PSUs awarded during the six months ended June 30, 2025 and through December 31, 2026 for the PSUs awarded during the six months ended June 30, 2024.  The actual number of shares of common stock underlying the PSUs to be earned will be between 0% and 125% of the target number of PSUs, depending on the level of achievement of such performance metrics.  The weighted-average fair value of the PSUs granted during the six months ended June 30, 2025 and 2024 was estimated to be $3.29 and $4.31 per PSU, respectively.  As of June 30, 2025, the Company determined that it was probable that the PSU grants will vest at 75% of the target number of PSUs for the PSUs granted in 2024 and 2025.  Stock-based compensation expense for the PSUs was $22 and $197 for the three months ended June 30, 2025 and 2024, respectively and $368 and $395 for the six months ended June 30, 2025 and 2024, respectively.

Employee Stock Purchase Plan

The ESPP allows eligible employees to purchase a number of shares of the Company’s common stock, through accumulated payroll deductions, up to a maximum of 15% of the employee’s earnings during a purchase period, as defined in the ESPP, subject to certain limitations. The purchase price will be the lesser of 85% of the fair market value of a share of Company common stock on (i) the beginning of each purchase period and (ii) the last day of the purchase period.  Purchase periods are generally six months in length.  

The most recent purchase period began on May 19, 2025.  The weighted average fair value for the shares estimated to be purchased under the ESPP for this purchase period was $0.70 per share, which the Company will expense over the current purchase period.

Stock-based Compensation Expense

The Company recorded stock-based compensation expense in the following expense categories of its unaudited condensed consolidated statements of operations:

​

​