But if he did it on his own time, he should have removed all personal documents and code when he left. If it was done on the companies equipment, it's still going to be theirs, not his to do with as they wish. If he wrote it on his own, and used it at work, under the GPL, then he might have a leg to stand on, but it will come down to the fineprint in his contract who owns code he wrote while employed full time by that company. Take it as a learning lession: Make sure you get signed contracts for everything. Also, it he still has the source written under the GPL, simply fork it and upload to source forge under a new project name. But then comes th ugly case of patents. If he used any proprietary technology, or systems similar to that of his employer, they may hold patents for that invention. Even if he wrote the code, tough. Here in NZ, we have specifically dissallowed software patents in out patent law. The belief is that copywrite is sufficient to stop blatant ripping off of your work. We have no patent trolls in the NZ software industry.