That's what I've always done. I've found that most employers have few issues with saying "these projects predate employment and we don't own or want them." In

That's what I've always done. I've found that most employers have few issues with saying "these projects predate employment and we don't own or want them." In one case, I had a clause that said "anything that increases my recognition in [area of tech] is now owned by the company." It was almost too broad but I managed to stay well within the bounds and never have a "questionable" project.