I know that many developers protect their work from deliberate claims of prior ownership. But, I suspect that many do not. There are three types of protection: copyright, patent, and trademark. Two of these, patents and trademarks, need to be registered to provide protection. Copyrights do not. A copyright will protect even if you don't register it. Registration will determine if you are truly the original author.
If I were a developer or author, I would at least copyright my work. It's easy to do. You just place a copyright mark on your work so that it can be obviously seen. If you want more protection, mail a copy of your work to yourself and keep it sealed. The postmark will give an indication of the date it was created. This is also good practice for patents and trademarks if you need to prove precedence of your work.
This link will tell you what protections copyrights give:
Check it out.
Bruce, K4TQL
