Good question. I've gotten conflicting legal advice. Some say I need full signed contributor agreements for everything, no matter the license, and some say that

Good question. I've gotten conflicting legal advice. Some say I need full signed contributor agreements for everything, no matter the license, and some say that's not needed at all. I opted for something in-between. Just a notice that could cover our ass in the future. Several big companies are working on submitting code, and so licensing there can get tricky... hence, just go overkill and never worry about it. ;)