That's one thing -- if you took a contract signed ten years ago that granted "training" rights and tried to use that for "AI training," a judge would likely fin

That's one thing -- if you took a contract signed ten years ago that granted "training" rights and tried to use that for "AI training," a judge would likely find that customary business usage has changed in that time and there was no "meeting of the minds" to support a grant of AI training rights. Take that same language and sign a contract with it today ... different story. (Interesting question for contract lawyers: if you take the contract from a decade ago and execute it today, does the usage at the time of contract drafting control, or the usage at signing? One would assume time of signing, but for an adhesion contract that might not have undergone substantive changes I think there's an interesting argument that the interpretation most favorable to the signer controls. Probably some case law out there addressing this.)