X0508 4 2023-09-28 0000811212 ThermoGenesis Holdings, Inc. THMO 0001669192 Xu Xiaochun 2711 CITRUS ROAD RANCHO CORDOVA CA 95742 1 1 1 CEO 0001738401 Boyalife Group, Inc. 2453 S. ARCHER AVE. SUITE B CHICAGO IL 60616 1 0 Common Stock 2023-09-28 4 C 0 654206 1.07 A 927121 I Held by Boyalife Group, Inc. Amendment 3 to 1st Amended & Restated Revolving Credit Agr. 1.07 2023-09-28 4 C 0 700000 D 2018-04-16 2023-12-31 Common Stock 654206 7494000 I Held by Boyalife Group, Inc. On September 28, 2023, Boyalife Group, Inc. converted an aggregate of $700,000 of outstanding interest under a Second Amended and Restated Convertible Promissory Note issued by Issuer in April 2018, as amended. After giving effect to the conversion, as of the date of this Form 4, there was $7,278,000 in principal and approximately $216,000 in accrued interest outstanding under the Convertible Promissory Note, all of which is convertible at a current conversion price of $1.07 per share, subject to downward adjustment in the event that the Issuer issues shares of common stock at a lower price. Boyalife Group, Inc. is 100% owned by Dr. Xiaochun Xu. /s/ Xiaochun Xu 2023-10-02