That's got to be much harder to police than a company which actually build, advertises and sells copyrighted material in the public domain.
Minor quibble: I think you want to say "public sphere". You're discussing Intellectual Property law, and "Public Domain" has a very specific meaning in that context- which does not apply to this case. I got very confused for a moment!
In most casual contexts, "public domain" the way you are using it would be totally fine.


