[glimcat]

Yeah.

There are plenty of risks ranging from the minimal (they waste a little bit of your time and you don't get paid) to rather extreme (they waste loads of your time for years and you lose your IP to legal wrangling).

Book a competent lawyer who has dealt with this sort of problem to nail it down and make sure the risk stays minimal. Ditto in the accountancy department. Everyone does their due diligence, everyone stays happy down the road.