Sensei Biotherapeutics (SNSE) Proxy filing summary

Executive summary

• Supplement provides unaudited pro forma condensed financials for Q1 2026, reflecting the conversion of Series B Preferred Stock into common stock following stockholder approval and Nasdaq listing requirements.

• Acquisition of Faeth Therapeutics completed in February 2026, with Series B Preferred Stock issued to Faeth stockholders and PIPE investors, raising $200 million in gross proceeds.

• Conversion of Series B Preferred Stock into approximately 24.4 million shares of common stock is expected three business days after the June 10, 2026 stockholder vote.

• Pro forma financials are illustrative and may not reflect actual post-conversion results due to preliminary assumptions and unaccounted costs.

• Forward-looking statements highlight risks related to conversion conditions, stockholder approval, and Nasdaq application.

Voting matters and shareholder proposals

• Stockholders will vote on the conversion of Series B Preferred Stock and other matters at the June 10, 2026 Annual Meeting.

• Board recommendations on all proposals remain unchanged from the Definitive Proxy Statement.

Board of directors and corporate governance

• Directors, executive officers, and certain employees are participants in the proxy solicitation for the Annual Meeting.