Case: "We consider here the ability of a copyright holder to dedicate certain work to free public use and yet enforce an open source copyright license to control the future distribution and modification of that work. " Later, "Copyright holders who engage in open source licensing have the right to control the modification and distribution of copyrighted material."
On Open Source licenses, "Open source licensing has become a widely used method of creative collaboration that serves to advance the arts and sciences in a manner and at a pace that few could have imagined just a few decades ago. "
[Jacobson v. Katzer, No. 06-CV-1905 (Fed.Cir. Aug. 13, 2008)]