I am developing open source project at github, licensed under apache 2.0 license. Somebody made fork of my project and added functionality that was not included in my project and it is licensed under apache 2.0 license as well. Can I merge changes from fork to my initial branch? My license headers contains:
Copyright *My Institution*
Can I add this header as well to files merged from fork?
Thanks for any help.
AFAIK, you can merge the changes from the fork into your code base.
You can add your institutions copyright notice to their files (to cover your changes to their files); you cannot remove their copyright notice from their files.
You can merge the changes back, but unless you actually contact the author of the fork and arrange for him to assign his copyright to you, you can not declare the added files to be copyright by your institution.
If you don't arrange for the author of the fork to assign his copyrights to you, your project will henceforth be covered by a patchwork of copyrights by different authors, and if you want to relicense in the future, you will need to contact any contributors whose work you merged without copyright assignment at that time.
It may be easier to ask him for copyright assignment now. On the other hand, he may not agree without some idea of a specific relicensing goal that you have in mind, because many contributors see the patchwork of copyrights as an important way of protecting the open-source nature of the software that they have contributed to.
(I, too, am not a lawyer.)