"not sure how you'd satisfy the condition without one" doesn't fit with "Of course it doesn't." Regarding the second point, code from ProjectA, released under

"not sure how you'd satisfy the condition without one" doesn't fit with "Of course it doesn't." Regarding the second point, code from ProjectA, released under the MIT license, which is in ProjectB is not subject to ProjectB's copyright. This was jeffmould's scenario, and this code is not subject to two licenses. The ProjectB developers must do some creative act to the code before they can assert copyright on the modified code. Copying code from multiple sources is then subject to both licenses. It is also possible that with enough changes ProjectB is no longer subject to the original copyright from ProjectA. Quoting from http://www.ca10.uscourts.gov/opinions/13/13-6181.pdf http://www.ca10.uscourts.gov/opinions/13/13-6181.pdf : > A corollary of the “sameness” requirement is that “[c]opying deleted or so disguised as to be unrecognizable is not copying.” See v. Durang, 711 F.2d 141, 142 (9th Cir. 1983); see also Int’l Ass’n of Machinists & Aerospace Workers, AFL-CIO v. Winship Green Nursing Ctr., 103 F.3d 196, 203 n.6 (1st Cir. 1996) (“Even if a work is copied, however, no copyright infringement exists if substantial changes render the work unrecognizable.”); Warner Bros. Inc. v. Am. Broad. Cos., Inc., 720 F.2d 231, 241 (2d Cir. 1983) (“‘[A] defendant may legitimately avoid infringement by intentionally making sufficient changes in a work which would otherwise be regarded as substantially similar to that of the plaintiff’s.’” (quoting 3 Nimmer on Copyright § 13.03[B] at 13-38.1 to -38.2 (1983)). Which means that you could, with sufficient changes to the code, revoke rights granted by the other license. This is how Berkeley extracted itself from the AT&T license for Unix.