From Fedora Project Wiki

Gneric license letter

It would make it easier to redistribute NAME in Fedora[1] if each source file contains a license header. None of the source code files contains a license header. Can you update the source files with license header and confirm that all the files are licensed LICENSE?

Check REVIEW and for details.

[1] https://fedoraproject.org/wiki/Packaging:LicensingGuidelines?rd=Packaging/LicensingGuidelines#License_Clarification