So I used to work for a company, being one of two employees that created a piece of software.
I was hired as an employee of the company with no share holding, and signed a fairly standard contract where my time and anything I created during the time I was employed belonged to the company.
Just recently, the company is selling it's product and the purchasing company has asked that all employees sign a IP Assignment Deed.
My understanding is that, since I've already assigned all IP to the company that I worked at, I don't have any legal rights to assign my IP to this new entity... well because, I don't actually own any of it.
Is it common for past employees (not shareholders or founders) to have to sign these when products are being purchased? I was made redundant 2 years ago.
Were I in your shoes I'd ask for an amount of consideration with what you believe is commensurate with a "reasonable" value. If this is a small sale, something like $10,000. If it's a large sale, $100-200,000.
The point being that if they want you to sign away your ownership rights (real or imagined) they have to give you something in return or it's not a legal contract.
Contracts absolutely require that both parties get something of value out of the exchange.
[1] http://study.com/academy/lesson/rules-of-consideration-in-co...