Ripasso della dottrina dell’assignor estoppel (AE) nel diritto brevettuale da parte della corte suprema USA (S.C., 29.06.2021, Minerva surgical c .Hologica e altri, n° 20-440).
L’AE è una difesa che impedisce di eccepire la invalidità del brevetto che si era in prcedenza ceduto (venduto).
Si tratta dunque di una preclusione del diritto di far valere fatti estintivi/modificativi della pretesa altrui, basata sul divieto di venire contra factum proprium.
E’ parte del più generale istituto dell’estoppel , tipico del common law.
La SC ribadisce la validità dell’istituto, fondato sulla necessità di coerenza nella condotta del dante causa: <<, we do not think, as Minerva claims, that contem-porary patent policy—specifically, the need to weed out bad patents—supports overthrowing assignor estoppel. In re-jecting that argument, we need not rely on stare decisis: “[C]orrect judgments have no need for that principle to prop them up.” Kimble v. Marvel Entertainment, LLC, 576 U. S. 446, 455 (2015). And we continue to think the core of as-signor estoppel justified on the fairness grounds that courts applying the doctrine have always given. Assignor estop-pel, like many estoppel rules, reflects a demand for con-sistency in dealing with others. See H. Herman, The Law of Estoppel §3 (1871) (“An estoppel is an obstruction or bar to one’s alleging or denying a fact contrary to his own pre-vious action, allegation or denial”). When a person sells his patent rights, he makes an (at least) implicit representation to the buyer that the patent at issue is valid—that it will actually give the buyer his sought-for monopoly.3 In later raising an invalidity defense, the assignor disavows that implied warranty. And he does so in service of regaining access to the invention he has just sold. As the Federal Cir-cuit put the point, the assignor wants to make a “represen-tation at the time of assignment (to his advantage) and later to repudiate it (again to his advantage).” DiamondScientific,848 F. 2d, at 1224; see supra, at 4. By saying one thing and then saying another, the assignor wants to profit doubly—by gaining both the price of assigning the patent and the continued right to use the invention it covers. That course of conduct by the assignor strikes us, as it has struck courts for many a year, as unfair dealing—enough to out-weigh any loss to the public from leaving an invalidity de-fense to someone other than the assignor.>>, p. 13-14.
In alcuni casi però non opera: precisamente quando non c’è ragione di ravvisare affidamento nell’avente causa: <<Still, our endorsement of assignor estoppel comes with limits—true to the doctrine’s reason for being. Just as we guarded the doctrine’s boundaries in the past, see supra, at 7– 8, 11–13, so too we do so today. Assignor estoppel should apply only when its underlying principle of fair dealing comes into play. That principle, as explained above, de-mands consistency in representations about a patent’s va-lidity: What creates the unfairness is contradiction. When an assignor warrants that a patent is valid, his later denial of validity breaches norms of equitable dealing. And the original warranty need not be express; as we have ex-plained, the assignment of specific patent claims carries with it an implied assurance. See supra, at 13. But when the assignor has made neither explicit nor implicit repre-sentations in conflict with an invalidity defense, then there is no unfairness in its assertion. And so there is no ground for applying assignor estoppel>>, p. 14-15.
L’affermazione della SC mi pare esatta.
la Sc offre alcuni casi di non operatività dell’AE:
i) un esempio <<of non-contradiction is when the assign-ment occurs before an inventor can possibly make a war-ranty of validity as to specific patent claims>>.
ii) un secondo esempio è << when a later legal development ren-ders irrelevant the warranty given at the time of assign-ment. Suppose an inventor conveys a patent for value, with the warranty of validity that act implies. But the governing law then changes, so that previously valid patents become invalid>.
III) un terzo esempio (il più stimolante teoricamente) è la modifica delle rivendicaizoni: <<another post-assignment develop-ment—a change in patent claims—can remove the ra-tionale for applying assignor estoppel. Westinghouse itself anticipated this point, which arises most often when an in-ventor assigns a patent application, rather than an issued patent. As Westinghouse noted, “the scope of the right con-veyed in such an assignment” is “inchoate”—“less certainly defined than that of a granted patent.” 266 U. S., at 352–353; see supra, at 9. That is because the assignee, once he is the owner of the application, may return to the PTO to “enlarge” the patent’s claims. 266 U. S., at 353;see 35 U. S. C. §120; 37 CFR §1.53(b). And the new claims result-ing from that process may go beyond what “the assignor in-tended” to claim as patentable. 266 U. S., at 353. Westing-house did not need to resolve the effects of such a change, but its liberally dropped hints—and the equitable basis for assignor estoppel—point all in one direction. Assuming that the new claims are materially broader than the old claims, the assignor did not warrant to the new claims’ va-lidity. And if he made no such representation, then he can challenge the new claims in litigation: Because there is no inconsistency in his positions, there is no estoppel. The lim-its of the assignor’s estoppel go only so far as, and not be-yond, what he represented in assigning the patent applica-tion>>, p. 15-16.
Si v. la sintesi, sempre utile, presente nell’iniziale Syllabus , come costume per le pronunce della SC.