tiffs asked for a declaration of the rights of the parties in the Superman character.
Referee J. Addison Young, in an opinion dated 21 November 1947, concluded that the March 1938 agreement was valid and that it transferred to Detective “all of plaintiffs’ rights to Superman” (emphasis added). Shortly thereafter, on 12 April 1948, the referee signed findings of fact and conclusions of law. The first such conclusion stated:
1. By virtue of the instrument of March 1, 1938, plaintiffs transferred to Detective Comics, Inc. all of their rights in and to the comic strip Superman including the title, names, characters and concept … and by virtue of said instrument Detective Comies, Inc. became the absolute owner of the comic strip Superman ….
On 19 May 1948 the parties signed a stipulation which called for the payment of certain moneys by National to plaintiffs. In addition the stipulation repeated the above-quoted conclusion of law, and also stated that:
Defendant National Comics Publications, Inc. is the sole and exclusive owner of and has the sole and excclusive right to the use of the title Superman and to the conception, idea, continuity, pictorial representation and formula of the cartoon feature Superman as heretofore portrayed and published … and such sole and exclusive ownership includes, but is not limited to, the fields of book and magazine publications, [etc.] and all other forms of reproduction and presentation, whether now in existence or that may hereafter be created, together with the absolute right to license, sell, transfer or otherwise dispose of said rights.
The final consent judgment filed by the referee on 21 May 1948 incorporated the above stipulation and further
Declared and Adjudged that by virtue of the instrument of March 1, 1938, plaintiffs validly transferred to Detective Comics, Inc. … all of their rights in and to the comic strip Superman … and that by virtue of said instrument, said Detective Comics, Inc. became the absolute owner of the comic strip Superman … and it is further
Declared and Adjudged that defendant National Comics Publications, Inc. is the sole and exclusive owner of and has the sole and exclusive right to the use of the title … and … cartoon feature Superman … and it is further
Ordered and Adjudged that plaintiffs … be and they hereby are enjoined and restrained from creating, publishing, selling or distributing … any material of the nature heretofore created, produced or published under the title Superman ….
Plaintiffs now seek a declaration that they, and not defendant National, own the copyright renewal rights to the Superman strip. National counterclaims for a similar declaration in its favor. It is stipulated that both parties made timely renewal filings with the Register of Copyright.
The court below granted defendants summary judgment dismissing the complaint, primarily for three reasons:
1) The 1947 Westchester action bars relitigation of questions concerning the rights of the parties in Superman, because of res judicata;
2) Superman was a “work for hire” within the meaning of the Copyright Act, 17 U.S.C. § 26 (Supp.1974), and therefore the renewal rights are in the employer;
3) the various agreements between the parties consistently manifested an intention to give to Detective all of plaintiffs’ rights in Superman, including the right of renewal of copyright, though it was never mentioned expressly in any of the agreements.
II
We are persuaded here that the court below properly decided that the state court judgment of May 21st, 1948 effectively estopped the plaintiffs from relitigating the issue of the ownership of