I posted some open source code on soureforge, and someone got in contact with me stating they intended to use my algorithms for a commercial product. I don't want this to happen, what should I do? According to us copyright.gov site:
"Your work is under copyright protection the moment it is created and fixed in a tangible form that it is perceptible either directly or with the aid of a machine or device."
Which seems to grant some legal protection by doing nothing. I looked at getting an official copyright from them, and its more than I'd like to spend ($135). Is that what I need to get for my work? Or are licenses a cheaper and safe/legal alternative? Or something else? Or nothing at all?