Background (Details)	Mar. 07, 2023
CARISMA Therapeutics Inc, Legacy, Stockholders \| Carisma Therapeutics Inc.
Background
Exchange ratio of shares of Sesen Bio for each share of Legacy Carisma	74.2
CARISMA Therapeutics Inc, Legacy, Stockholders \| Sesen Bio, Inc. \| Carisma Therapeutics Inc.
Background
Common stock at an exchange ratio	1.8994
Sesen Bio Stockholders \| Sesen Bio, Inc.
Background
Ownership interest held after the merge	25.80%

Ratio of converted into shares common stock at an exchange ratio.

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