I am not sure if this is a contract questsion or a ip question.
A friend sort of had an idea for a computer program. We agreed I would write it and he would market it. Like a dope I did not get the agreement in writing.I spend hours on research and adding additional features to the idea.
When I insisted that our agreement of a 50/50 split be in writing, we could not come to an agreement at all.
My questions is 1) can I market it on my own one when I finish it and 2) does he have any legal claim to it at all.
I think for what it is worth, since I have done about 90% of the work and added additional things to the idea, it is mine to do with as I please.
PS: I live in California.