Certara, Inc.

Trading Plans

Our directors and officers may adopt written plans, known as Rule 10b5-1 plans, in which they will contract with a broker to buy or sell our common stock on a periodic basis. Under a Rule 10b5-1 plan, a broker executes trades pursuant to parameters established by the director or officer when entering into the plan, without further direction from them.

During the three months ended June 30, 2025, none of our directors or officers (as defined in Rule 16a-1(f) of the Exchange Act)adopted orterminated a Rule 10b5-1 trading plan.

Adoption of Second Amended and Restated Bylaws

On August 5, 2025, our Board of Directors approved an amendment and restatement of our Bylaws, effective August 5 2025, primarily to (i) add procedural and informational requirements for stockholders that intend to use the rule pertaining to universal proxy cards set forth in Rule 14a-19 of the Exchange Act (the “Universal Proxy Rule”) and (ii) make other administrative changes primarily to reflect recent Delaware law developments, in each case as further described below.

Advance Notice Amendments: The advance notice amendments require stockholders to make certain representations to the Company, certify compliance with the Universal Proxy Rule, and submit nominee questionnaires to the Secretary of the Company.

Administrative Amendments: Our Board of Directors also approved certain administrative amendments to the Bylaws to conform the provisions related to (i) notices of adjournments, including with respect to remote meetings of stockholders, and (ii) stockholder lists, in each case to updated Delaware law provisions. In addition, these administrative amendments provide that any stockholder soliciting proxies from other stockholders must use a proxy card color other than white, which color is reserved for the exclusive use by the Board. Finally, the administrative amendments also included conforming references from a nonoperative stockholders agreement to the operative stockholders agreement between the Company and affiliates of Arsenal Capital Partners.

The foregoing description is qualified in its entirety by reference to the Second Amended and Restated Bylaws, which are filed hereto as Exhibit 3.3 and incorporated herein by reference.