id. at 122, 76 S.Ct. 663); see also Communist Party of U.S. v. Subversive Activities Control Board, 367 U.S. 1, 70–72, 81 S.Ct. 1357, 6 L.Ed.2d 625 (1961) (returning, after remand, to only those constitutional issues “properly before” the Court, id. at 72, 81 S.Ct. 1357).
We turn, then, to the fair use defense, which provides that “the fair use of a copyrighted work, including such use by reproduction in copies … for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright.” 17 U.S.C. § 107. When considering whether a particular use is fair, courts must consider the following factors:
(1) the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;
(2) the nature of the copyrighted work;
(3) the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and
(4) the effect of the use upon the potential market for or value of the copyrighted work.
Id. “The factors enumerated in the section are not meant to be exclusive: ‘[S]ince the doctrine is an equitable rule of reason, no generally applicable definition is possible, and each case raising the question must be decided on its own facts.” Harper & Row Publishers, Inc. v. Nation Enterprises, 471 U.S. 539, 560, 105 S.Ct. 2218, 85 L.Ed.2d 588 (1985) (alteration in original) (quoting H.R. Rep. No. 94-1476, at 65 (1976), as reprinted in 1976 U.S.C.C.A.N. 5659, 5678). The end of this quotation bears repeating: each case raising a fair use defense must be decided on its own facts.
In the district court, PRO argued that its distribution of the incorporated standards was in pursuit of the Act’s enumerated fair use purposes—to facilitate criticism and comment—and explained why the statutory fair use factors supported the conclusion that its reproduction was fair use, especially because the reproduced works were incorporated by reference into the law. The district court rejected PRO’s claimed purpose. Instead, it flatly concluded that PRO’s “distribution of identical copies of copyrighted works [was] for the direct purpose of undermining [the SDOs’] ability to raise revenue” and “nothing in the Copyright Act or court precedent” suggests that such use of copyrighted works “can ever be a fair use. ASTM, 2017 WL 473822, at *18 (emphasis added). Reviewing de novo, however, we see nothing in the record that supports the district court’s blanket conclusion that PRO distributed copies of the incorporated standards solely to “undermin[e] [the SDOs’] ability to raise revenue.” Id. Rather, by all accounts, PRO distributed these standards for the purpose of educating the public about the specifies of governing law. See PRO Br. 43 (explaining that “[t]here is no better way to teach the law to the public than to provide the public with the law”); ASTM Br. 34 (“PRO’s purpose is to enable members of the public to obtain copies of [the standards].”). More fundamentally, the district court failed to account for the variation among the standards at issue and afford due consideration to the particular legal status of each incorporated work. That is, it failed to consider each fair use claim “on its own facts.” Harper & Row, 471 U.S. at 560, 105 S.Ct. 2218 (internal quotations and citations omitted).
In this section, we review each of the fair use factors, and, as we shall explain, though there is reason to believe “as a matter of law” that PRO’s reproduction of certain standards “qualif[ies] as a fair use of the copyrighted work,” id. (internal quotations and citations omitted), we ultimately think the better course is to remand the case for the district court to further devel-
