Form 4: CytomX CEO Sells Shares for Tax Obligations

CytomX Therapeutics CEO Sean A. McCarthy sold 118,969 shares of common stock to cover tax obligations related to RSU vesting.

Summary

• Sean A. McCarthy, CEO and Director of CytomX Therapeutics, Inc. (CTMX), reported a transaction on March 17, 2026.
• McCarthy disposed of 118,969 shares of Common Stock at a price of $6.423 per share.
• The sale was executed solely to satisfy tax or other government withholding obligations associated with the vesting of restricted stock units (RSUs).
• Following the transaction, McCarthy directly beneficially owns 1,078,922 shares, which includes 457,500 RSUs.
• Additionally, 93,158 shares are indirectly beneficially owned through the Sean A. McCarthy 2018 Trust, where McCarthy serves as trustee.

Sentiment

Score: 5

Explanation: StockSavvy.ai views this as a neutral event. The sale is explicitly stated to be for tax withholding purposes related to RSU vesting, which is a common and non-discretionary transaction for executives receiving equity compensation.

Future Outlook

This filing does not contain any forward-looking statements or guidance regarding the company's future performance or outlook.

Industry Context

StockSavvy.ai notes that insider transactions, particularly those related to covering tax obligations from RSU vesting, are a routine aspect of executive compensation and do not typically signal a change in management's confidence in the company's prospects. Such sales are often pre-scheduled under Rule 10b5-1 plans.

Stakeholder Impact

• Shareholders: Minimal impact, as this is a routine, non-discretionary sale for tax purposes and not indicative of a change in management's view of the company's value.

Key Dates

Recommendation

A seasoned investor or institution would likely maintain a 'hold' recommendation based on this filing. The transaction is a non-discretionary sale to cover tax obligations from RSU vesting, which is a standard practice for executives. It does not reflect a change in the CEO's investment thesis or the company's fundamental outlook, nor does it suggest any new material information about the company's performance or prospects.

Keywords

CTMX, CytomX Therapeutics, Form 4, insider transaction, stock sale, RSU vesting, tax obligations, Sean A. McCarthy