I think I understand why the Free Software Foundation insists that a license is not a contract. Their belief is grounded upon a mistaken interpretation of the case law on licensing patents, highlighted in a 1938 decision by the Supreme Court in General Talking Pictures Corp. v. Western Electric Co., Inc., 305 U.S. 124
"The question of law requiring decision is whether the restriction in the license is to be given effect. That a restrictive license is legal seems clear. Mitchell v. Hawley, 16 Wall. 544. As was said in United States v. General Electric Co., 272 U.S. 476, 489 , 47 S.Ct. 192, 196, the patentee may grant a license 'upon any condition the performance of which is reasonably within the reward which the patentee by the grant of the patent is entitled to secure.' The restriction here imposed is of that character. The practice of granting licenses for a restricted use is an old one, see Providence Rubber Company v. Goodyear, 9 Wall. 788, 799, 800; Gamewall Fire-Alarm Telegraph Co. v. Brooklyn, C.C., 14 F. 255. So far as appears, its legality has never been questioned. The parties stipulated that 'it is common practice where a patented invention is applicable to different uses, to grant written licenses to manufacture under United States Letters Patents restricted to one or more of the several fields of use permitting the exclusive or non-exclusive use of the invention by the licensee in one field and excluding in another field."
The phrase above, "the patentee may grant a license 'upon any condition the performance of which is reasonably within the reward which the patentee by the grant of the patent is entitled to secure.' refers to the fact that any condition imposed in a "bare" license (no contractual terms) may restrict only the use of the exclusive rights ("reward") of the patentee. The patentee alone is the only person who can restrict his exclusive rights.
The phrase quoted above does not apply analogously to all "exclusive rights" in derivative copyrighted works. In patent law there is no such thing as a "derivative patent" defined as two distinct legal parties owning independent exclusive rights in the same idea.
Sec. 103 (b) The copyright in a compilation or derivative work extends only to the material contributed by the author of such work... The copyright in such work is independent of, and does not affect or enlarge the scope, duration, ownership, or subsistence of, any copyright protection in the preexisting material.
An original author has an exclusive right to commission a derivative work, but his exclusive rights encompass only his preexisting work in the commissioned work. The original author must "bargain" for the modifying author's exclusive rights. They exist independently of the original author's exclusive rights and hence do not fall under the scope of a "bare" license. They are not "within the reward which the copyright holder by the grant of the copyright is entitled to secure" of the original author.
A summary of the above reasoning is "a unilateral grant of permission for a derivate copyright work does not exist within the scope of the definition of a 'bare' license."
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