You need to have an active contract with them, you need to pay a fee to be able to use their seeds. If you don’t have an active contract with them, you don’t have permission to use their seeds, they’ll send their goons around to inspect your plants, if they find what looks like a crop grown from their seeds, they’ll sue you, they don’t care how it got there, they’ll just sue you anyways. Other people around the area could also snitch on you.
Here’s the thing, you can actually just ignore the laws, and as long as you keep your fucking mouth shut, you’ll be fine.