“The governor has until September 30 to sign or veto legislation in his/her possession on the day the legislature adjourns (usually August 31), or it becomes law without being signed.”

https://www.statescape.com/resources/legislative/bill-signing-deadlines/

“California’s governor has the chance to make AI history“

https://www.vox.com/future-perfect/369628/ai-safety-bill-sb-1047-gavin-newsom-california.

Note: I don’t think this is one of the instances where line-by-line veto is applicable, but for the sake of establishing resolution criteria just in case, I am referring to the bill as a whole. If there are certain parts that are vetoed, but it otherwise survives, the market will resolve as one of the other non-veto options.