[qwertyuiop12]

In general, I try to add a fingerprint into the output.

For example, in a project which generates images I usually set a specific set of pixels.

[tombert]

Sure, but if they have access to your code then a company could pay a junior engineer to look for any kinds of explicit fingerprints and remove it.

[ValentineC]

Some companies that steal open source code are likely to cheap out on even this.