Revolution Medicines, Inc.

Evaluation of disclosure controls and procedures

Our management, with the participation of our President, Chief Executive Officer and Director and our Chief Financial Officer, our principal executive officer and principal financial officer, respectively, has evaluated our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended) as of September 30, 2026. Based on the evaluation, our President, Chief Executive Officer and Director and our Chief Financial Officer have concluded that, as of September 30, 2026, our disclosure controls and procedures were, in design and operation, effective to the reasonable assurance level.

Changes in internal control over financial reporting

In connection with the commercial launch of RASONQUE in August 2026, we implemented new processes and internal controls over financial reporting relating to revenue recognition, including the estimation of variable consideration; order-to-cash, including customer onboarding, order processing, shipping and billing; the accumulation and review of distributor and specialty pharmacy sales and inventory data; inventory costing and valuation; and accounts receivable and credit loss estimation. Other than the foregoing, there were no changes in our internal control over financial reporting identified in connection with the evaluation required by Rules 13a-15(d) and 15d-15(d) of the Exchange Act that occurred during the three months ended September 30, 2026 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Inherent limitation on the effectiveness of internal control over financial reporting

The effectiveness of any system of internal control over financial reporting, including ours, is subject to inherent limitations, including the exercise of judgment in designing, implementing, operating, and evaluating the controls and procedures, and the inability to eliminate misconduct completely. Accordingly, any system of internal control over financial reporting, including ours, no matter how well designed and operated, can only provide reasonable, not absolute, assurances. In addition, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate. We intend to continue to monitor and upgrade our internal controls as necessary or appropriate for our business, but there can be no assurance that such improvements will be sufficient to provide us with effective internal control over financial reporting.