Post-sale restraint

A post-sale restraint, also termed a post-sale restriction, as those terms are used in United States patent law and antitrust law, is a limitation that operates after a sale of goods to a purchaser has occurred and purports to restrain, restrict, or limit the scope of the buyer’s freedom to utilize, resell, or otherwise dispose of or take action regarding the sold goods. Such restraints have also been termed "equitable servitudes on chattels."

Support for the rule against enforcement of post-sale restraints has at times been rested on the common law's hostility to restraints on the alienation of chattels. "The right of alienation is one of the essential incidents of a right of general property in movables, and restraints upon alienation have been generally regarded as obnoxious to public policy, which is best subserved by great freedom of traffic in such things as pass from hand to hand. General restraint in the alienation of articles, things, chattels, except when a very special kind of property is involved, . . . have been generally held void."

Perhaps the earliest US discussion of post-sales restraints occurs in Adams v. Burke, in which the US Supreme Court refused to find patent infringement when an undertaker — who purchased a patented coffin lid, and transported it outside the territory in which the manufacturer was licensed (the ten-mile radius surrounding Boston) — used the product to bury a client. The Court stated:

But in the essential nature of things, when the patentee, or the person having his rights, sells a machine or instrument whose sole value is in its use, he receives the consideration for its use and he parts with the right to restrict that use. The article, in the language of the Court, passes without the limit of the monopoly. That is to say the patentee or his assignee having in the act of sale received all the royalty or consideration which he claims for the use of his invention in that particular machine or instrument, it is open to the use of the purchaser without further restriction on account of the monopoly of the patentees.

On the basis of this doctrine, in Motion Picture Patents Co. v. Universal Film Mfg. Co., the Supreme Court refused to enforce by way of a patent infringement suit against a downstream purchaser an agreement requiring that a patented film projector be used only with films licensed by the Motion Picture Patents Co., that the same agreement be imposed on downstream purchasers, and that the machine be sold with a plate affixed to it stating the same requirement.

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Wikipedia