Form 4 Filing for BEST SPAC I Acquisition Corp.

On September 29, 2026, Yun Chen, a 10% owner of BEST SPAC I Acquisition Corp. (BSAA), sold all of his interests in the sponsor of the Issuer, BEST SPAC I (Holdings) Corp., to A SPAC (Holdings) Group Corp. for $1. This transaction resulted in Chen no longer having any voting or dispositive power over the Issuer's securities previously held by the sponsor. The filing indicates a disposition of Class A ordinary shares (277,000), Class B ordinary shares (1,375,000), and rights to receive Class A ordinary shares (277,000). Post-transaction, Chen owns 0 shares of Class A ordinary shares, 0 Class B ordinary shares, and 0 rights. The Class B shares are convertible into Class A shares, and the rights entitle the holder to Class A shares upon the Issuer's initial business combination.