附件2.2

參與協議

這份參與協議，係由以下各方於2024年9月16日締結：入社協議Keen Vision Acquisition Corporation，一家英屬維爾京群島商業公司（母公司），Medera Inc.，一家開曼群島獲豁免公司（權益代理”), KVAC (Cayman) Limited, a Cayman Islands exempted company and wholly owned subsidiary of the Parent (“收購方”) and KVAC MS (Cayman) Limited, a Cayman Islands exempted company and wholly owned subsidiary of Acquirer (“合併子公司”). Reference is made to that certain Merger Agreement (the “合併協議”), dated as of September 3, 2024, entered into by and between Parent and the Company. Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to such terms in the Merger Agreement.

WHEREAS, Acquirer was formed on August 28, 2024 for the sole purpose of the merger of Parent with and into Acquirer, in which Acquirer will be the surviving entity;

鑒於，Merger Sub於2024年7月10日成立，其唯一目的為與公司合併，使公司成為Acquirer的存續實體，並成為Acquirer的全資子公司；

鑒於，根據變速器協議，Acquirer和Merger Sub需要簽署並交付本加入協議； 7.6條項允許的投資 鑒於，本協議各方希望根據本加入協議簽署本加入協議，使Acquirer和Merger Sub各自成為變速器協議的一方；

鑒於，本協議各方希望僅修改變速器協議中明確列出的那些條款；

現以前述互相承諾及其他有價值的考慮作為條件，就本加入協議各方一致同意如下：

合約約束

1. 合約約束收購方和併購子公司均同意，在簽署本加入協議書後，即成為併購協議的一方，並將完全受併購協議的所有條款、條件、陳述、保證、權利、義務和條件約束，如同原始締約方一樣。母公司和公司均同意此加入及導致併購協議的修訂。

2. 繼承人及受讓人本加入協議書應對當事方及其各自的繼受人和受讓人具有約束力。

3. 整個協議本加入協議書代表當事方就本主題之間的整個協議，除非本加入協議書或併購協議中明確規定，否則據此解除所有先前就該主題進行的談判、陳述或協議，無論口頭或書面。

4. 對照合約本加入協議書可以分開以副本形式簽署，每一份副本均為正本，全部副本一起構成同一協議。本加入協議書可以通過傳真或電子傳輸方式簽署和交付。

5. 管轄法 . This Joinder Agreement and any claim, controversy or dispute arising under or related to this Joinder Agreement shall be governed by and construed in accordance with the laws of the State of Delaware applicable to contracts made and to be performed wholly within such State (including in respect of the statute of limitations or other limitations period applicable hereto), and without regard to the conflicts of laws principles thereof. Any dispute relating to this Agreement shall be resolved in accordance with the Dispute Resolution provisions set forth in Section 12.8 of the Merger Agreement.

6. 標題. The headings contained in this Joinder Agreement are for convenience of reference only and shall not be deemed to alter or affect any provision hereof.

[以下為簽名頁面]

IN WITNESS WHEREOF, the parties hereto have caused this Joinder Agreement to be effective as of the date first written above.