There's a big difference between granting the school a non-exclusive copyright licence (including one that allows them to sublicense to anti-plagiarism companies), and assigning them your copyright. I'd be happy to do the first, but not the second.
> is it even possible to grant a non-exclusive, non-revocable license?
...Yes?
IAN(Y)AL. But licences aren't revocable by default. If I grant you a licence by contract, then you have a licence. If I want to revoke it, I have two options.
- One, I can ask you if you'd be willing to waive/vary the contract, in return for some good consideration. But you don't have to accept.
- Two, I can send you a letter saying "I revoke your licence", sue you, and crucially, try to convince a judge to imply a term into the contract that allows me to revoke the license. Which is pretty hard. Terms aren't implied lightly. Especially if I put the word "irrevocable" in the contract, no-one's going to imply a clause saying the exact opposite.
Important thing: "by contract". If I grant you a licence gratuitously, outside of a contract or deed, that's different.
