[The text below was composed based on 1.2. License section of curl/libcurl project.]
When contributing with code, you agree to put your changes and new code under the same license nghttp2 is already using unless stated and agreed otherwise.
When changing existing source code, you do not alter the copyright of the original file(s). The copyright will still be owned by the original creator(s) or those who have been assigned copyright by the original author(s).
By submitting a patch to the libhttp2 project, you are assumed to have the right to the code and to be allowed by your employer or whatever to hand over that patch/code to us. We will credit you for your changes as far as possible, to give credit but also to keep a trace back to who made what changes. Please always provide us with your full real name when contributing!