Cyclerion Therapeutics, Inc. Stock Compensation Disclosure

7. Share-based Compensation Plans

In 2019, Cyclerion adopted share-based compensation plans. Specifically, Cyclerion adopted the 2019 Employee Stock Purchase Plan (“2019 ESPP”) and the 2019 Equity Incentive Plan (“2019 Equity Plan”). Under the 2019 ESPP, eligible employees may use payroll deductions to purchase shares of stock in offerings under the plan, and thereby acquire an interest in the future of the Company. The 2019 Equity Plan provides for stock options, restricted stock awards ("RSAs") and restricted stock units (“RSUs”).

Cyclerion also mirrored two of Ironwood Pharmaceuticals, Inc. ("Ironwood") existing plans, the Amended and Restated 2005 Stock Incentive Plan (“2005 Equity Plan”) and the Amended and Restated 2010 Employee, Director and Consultant Equity Incentive Plan (“2010 Equity Plan"). These mirror plans were adopted to facilitate the exchange of Ironwood equity awards for Cyclerion equity awards upon the Separation as part of the equity conversion. As a result of the Separation and in accordance with the EMA, employees of both companies retained their existing Ironwood vested options and received a pro-rata share of Cyclerion options, regardless of which company employed them post-Separation. For employees that were ultimately employed by Cyclerion, unvested Ironwood options and RSUs were converted to unvested Cyclerion options and RSUs.

Stock Options

Stock options granted under the Company’s equity plans generally have a ten-year term and vest over a period of four years, provided the individual continues to serve at the Company through the vesting dates. Options granted under all equity plans are exercisable at a price per share not less than the fair market value of the underlying common stock on the date of grant. The estimated fair value of options, including the effect of estimated forfeitures, is recognized over the requisite service period, which is typically the vesting period of each option.

During the years ended December 31, 2025 and 2024, the Company granted stock options to purchase an aggregate of 25,000 shares and 55,849 shares, respectively, at weighted average grant date fair values per option share of $2.14 and $2.80 respectively.

There were no options exercised during the year ended December 31, 2025 and 2024.

As of December 31, 2025, the unrecognized share-based compensation expense, net of estimated forfeitures, related to all unvested time-based stock options held by the Company’s employee and non-employees is $0.1 million and the weighted average period over which that expense is expected to be recognized is 3.03 years.

For the years ended December 31, 2025 and 2024, expected volatility was estimated using an average of the historical volatility of the common stock of a group of similar companies that were publicly traded. The Company will continue to apply this process until a sufficient amount of historical information regarding the volatility of its own stock price becomes available.

The Company has granted certain employees performance-based options to purchase shares of common stock. These options are subject to performance-based milestone vesting. During the year ended December 31, 2025 and 2024, there were no shares that vested as a result of performance milestone achievements. No share-based compensation expense related to these performance-based options was recognized during the years ended December 31, 2025, and 2024, respectively.

Restricted Stock Awards

No RSA was granted during the year ended December 31, 2025. The Company granted 65,000 RSAs during the year ended December 31, 2024. The fair value of all RSAs is based on the market value of the Company’s common stock on the date of grant. Compensation expense, including the effect of estimated forfeitures, is recognized over the applicable service period.

As of December 31, 2025, the unrecognized share-based compensation expense, net of estimated forfeitures, related to all unvested RSAs held by the Company’s directors is $0.2 million and the weighted average period over which that expense is expected to be recognized is 1.69 years.