Waystar Holding Corp

(a)On November 4, 2024, a sub-committee of the Compensation Committee of the Board of Directors of the Company approved an amendment to the outstanding option awards granted to our executive officers, including each of our named executive officers, under the 2019 Stock Incentive Plan (the “Amendment”). The Amendment modifies the alternative vesting terms pursuant to which performance-vesting options may vest following the 18-month anniversary of our initial public offering (the “IPO”).

Specifically, the Amendment provides that, from and after the date of the first trading window that commences after the 18-month anniversary of the IPO through the final measurement date, the performance-vesting options will be eligible to vest upon the first day of each trading window (each, an “Open Window Commencement Date”), subject to the participant’s continued employment through such date, based on the achievement of the following performance hurdles (the “Alternative Performance Hurdles”):

The Amendment provides that the number of performance-vesting options that vest on each such Open Window Commencement Date will be reduced by the number of performance-vesting options that have previously vested prior to such Open Window Commencement Date. The Alternative Performance Hurdles replace the provisions in place prior to the Amendment that would have treated the 20-Day VWAP as of an Open Window Commencement Date following the 18-month anniversary of the IPO as deemed cash proceeds for purposes of determining the achievement of the sponsor multiple of investment performance vesting objectives. The Amendment is not expected to have a material impact to the financial statements.

The foregoing description of the Amendment does not purport to be complete and is subject to, and qualified in its entirety by, the full text of the Amendment, a copy of which is filed as Exhibit 10.1 to this Quarterly Report on Form 10-Q and is incorporated by reference herein.

(b)During the three months ended September 30, 2024, the following officer and director trading plan arrangement changes occurred:

(1)On September 6, 2024, Steve Oreskovich, our Chief Financial Officer, adopted a trading plan intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). Mr. Oreskovich’s plan provides for (i) the exercise of 49,998 vested stock options and the associated sale of up to 49,998 shares of the Company’s common stock and (ii) the sale of up to 30,434 shares of the Company’s common stock issuable upon vesting of time-based vesting restricted stock units (“RSUs”). Mr. Oreskovich’s trading plan will expire on December 31, 2025 or upon the earlier sale of all of the shares subject to the plan.

(2) Each of the officers listed below entered into a trading arrangement (a “sell-to-cover arrangement”) that is intended to qualify as an “eligible sell-to-cover transaction” (as described in Rule 10b5-1(c)(1)(ii)(D)(3) under the Exchange Act) and to satisfy the affirmative defense conditions of Rule 10b5-1(c) on the date set forth opposite such officer’s name. Each sell-to-cover arrangement applies to RSUs. Each sell-to-cover arrangement provides for the automatic sale of shares of the Company’s common stock for each settlement date of a covered RSU in an amount necessary to satisfy the applicable withholding obligations. The number of shares that will be sold under the sell-to-cover arrangements is not currently determinable as the number will vary based on the extent to which vesting conditions are satisfied and the market price of our common stock at the time of settlement. These sell-to-cover arrangements will remain in effect until terminated by the participating officer or the Company.