There are a lot of unknowns with your post, which makes useful feedback difficult. The answer could range anywhere from "don't worry about it" to "hammer out an

There are a lot of unknowns with your post, which makes useful feedback difficult. The answer could range anywhere from "don't worry about it" to "hammer out an agreement with the other parties first." Are you looking to run with the concept, or are you hoping to build off of code already written? In either event, I'd strongly suggest speaking to a qualified attorney before doing anything. At the very least, you'll want them to review any contracts you signed, walk you through your possible exposure, and give you some recommendations for either minimizing or managing it. It's not a cheap move by any means, but if you genuinely want to move forward with this project, it'll help you avoid possible long-term problems.