The fair use four factors come from Section 107 of the Copyright Act, and courts weigh all four together whenever someone argues that an unauthorized use of copyrighted material is legally permitted.1Office of the Law Revision Counsel. 17 U.S. Code 107 – Limitations on Exclusive Rights: Fair Use The factors are the purpose and character of the use, the nature of the copyrighted work, the amount and substantiality of what was taken, and the effect on the market for the original. No single factor decides the case, and the statute lists uses like criticism, comment, news reporting, teaching, scholarship, and research as examples that may qualify, but the label alone never settles the question. Outcomes depend on how the four factors play out against the specific facts.
Who Has to Prove Fair Use
Fair use is an affirmative defense. If a copyright holder shows they own a valid copyright and that you copied it, the burden shifts to you to justify the use. The Supreme Court confirmed this framework in Campbell v. Acuff-Rose Music, Inc. (1994).2Justia. Campbell v. Acuff-Rose Music, Inc. Courts don’t hunt for reasons to excuse unauthorized copying. You have to raise fair use, and you have to support it factor by factor.
Section 107 sets a floor for the analysis, not a ceiling. Judges can weigh other considerations, the factors interact, and a strong showing on one can sometimes offset weakness on another. That flexibility is also why fair use outcomes are genuinely hard to predict.3U.S. Copyright Office. About the U.S. Copyright Office Fair Use Index
Factor One: Purpose and Character of the Use
The first factor asks what you did with the material and why. Courts look for “transformative” use, meaning the copy serves a different purpose or adds a new character rather than substituting for the original. Commercial use doesn’t automatically defeat fair use, but it raises the bar for showing that your purpose was genuinely distinct from the copyright holder’s.3U.S. Copyright Office. About the U.S. Copyright Office Fair Use Index
In Campbell, the Supreme Court held that 2 Live Crew’s parody of Roy Orbison’s “Oh, Pretty Woman” could qualify as fair use despite being sold for profit. Parody, the Court said, has to borrow from the original to make its point, and the group’s version carried a message different from Orbison’s romantic ballad.2Justia. Campbell v. Acuff-Rose Music, Inc.
For nearly three decades after Campbell, lower courts often read “transformative” broadly, sometimes finding fair use whenever a new work added any new meaning or expression. The Supreme Court narrowed that reading sharply in Andy Warhol Foundation for the Visual Arts, Inc. v. Goldsmith (2023). By a 7–2 vote, the Court ruled that licensing Andy Warhol’s silkscreen portrait of Prince to a magazine was not fair use, even though the artwork looked visibly different from Lynn Goldsmith’s original photograph.4Justia. Andy Warhol Foundation for Visual Arts, Inc. v. Goldsmith
Justice Sotomayor’s majority opinion rejected the idea that adding new expression or meaning is enough on its own to make a use transformative. Reading Campbell that way, the Court said, would swallow the copyright holder’s exclusive right to create derivative works, because most adaptations add something new. The analysis has to focus on the specific use being challenged, not the secondary work in the abstract. Warhol’s silkscreen might have been transformative in a museum context, but licensing it to illustrate a magazine article about Prince served “substantially the same” purpose as Goldsmith’s original photograph. When the use is commercial and serves a similar purpose, the Court said, a “particularly compelling justification” is required.
Warhol didn’t abolish transformative use. It tightened the test. If your use competes in the same market channel as the original, factor one now demands a real difference in purpose, not just a different look or feel.
Factor Two: Nature of the Copyrighted Work
The second factor asks what kind of work was copied. Factual material like news articles and technical reports gets thinner protection because the public has a strong interest in the free flow of facts. Novels, songs, films, and other highly creative works sit closer to the core of what copyright protects.3U.S. Copyright Office. About the U.S. Copyright Office Fair Use Index
Unpublished works get an additional layer of protection. In Harper & Row v. Nation Enterprises (1985), The Nation Magazine obtained a copy of President Gerald Ford’s unpublished memoir and built a 2,250-word article around 300 to 400 words of direct quotes. The Supreme Court rejected fair use, emphasizing an author’s right to control when and how their work first reaches the public.5Justia U.S. Supreme Court Center. Harper and Row v. Nation Enterprises The memoir dealt with newsworthy events, but the unpublished status tilted this factor heavily toward the copyright holder.
This factor usually carries less weight than the other three, but it can matter significantly when the work is unpublished or when it sits toward the creative end of the spectrum.
Factor Three: Amount and Substantiality
The third factor looks at how much you took, measured both by quantity and by significance. Taking a small portion favors fair use. Taking the whole work cuts against it, though not always fatally. The real danger is taking the “heart” of a work, even when the raw word count is low.3U.S. Copyright Office. About the U.S. Copyright Office Fair Use Index
Harper & Row is the classic illustration. The Nation’s 300-to-400 word excerpt was a tiny fraction of Ford’s full manuscript, but the Court found those words captured the most revealing and commercially valuable passages in the book. Qualitative significance mattered more than percentage.6Supreme Court of the United States. Harper and Row v. Nation Enterprises
On the other end, Sony Corp. of America v. Universal City Studios (1984) involved copying entire television broadcasts. The Supreme Court still found fair use because home viewers were recording shows for personal, noncommercial time-shifting, not redistributing them, and there was no meaningful market harm.7Justia U.S. Supreme Court Center. Sony Corp. of America v. Universal City Studios, Inc. Copying everything can survive scrutiny, but only when the purpose is narrow and noncommercial and the market isn’t harmed.
Factor Four: Effect on the Market
The fourth factor asks whether your use harms the copyright holder’s ability to profit from the work. Courts consider both actual lost revenue and what would happen if your kind of use became widespread. When the copy serves as a direct substitute for the original, this factor almost always sinks a fair use defense.1Office of the Law Revision Counsel. 17 U.S. Code 107 – Limitations on Exclusive Rights: Fair Use
In Authors Guild v. Google, Inc. (2015), the Second Circuit found Google’s massive book-scanning project qualified as fair use even though it digitized millions of copyrighted books without permission. Google only displayed brief “snippets” in search results, and the court held they were too fragmented to substitute for buying the books. The searchable database served a fundamentally different purpose from reading the works themselves.8Justia. Authors Guild v. Google, Inc.
Lost licensing revenue counts too, not just lost sales. If a functioning licensing market exists for the kind of copying you did, bypassing it weighs against you. In American Geophysical Union v. Texaco Inc. (1994), the Second Circuit rejected Texaco’s fair use defense partly because the Copyright Clearance Center already offered a straightforward licensing mechanism for photocopying journal articles. Texaco scientists were photocopying entire articles for their own files, and the court found those copies served the identical function as additional licensed copies.9Justia. American Geophysical Union v. Texaco Inc.
How the Factors Work Together
The factors interact, and certain fact patterns reliably sink fair use defenses regardless of how the individual factors look on paper.
Systematic copying to avoid paying for subscriptions or licenses is one. Texaco illustrates the pattern: internal photocopies replaced what would otherwise have been licensed copies, and a licensing market existed.
Scooping unpublished works is another. Harper & Row failed in part because The Nation timed its article to beat a licensed excerpt that Time Magazine had already paid for. Time cancelled its piece and refused to pay the remaining $12,500 of its licensing fee, giving the Court concrete evidence of market harm.5Justia U.S. Supreme Court Center. Harper and Row v. Nation Enterprises
After Warhol, commercial uses that occupy the same market channel as the original face a higher climb even when the new work adds fresh expression. If the copy competes with the original as a product, factor one and factor four often reinforce each other against fair use.
What It Costs to Lose
Losing a fair use defense means you are liable for copyright infringement. Copyright holders can recover either their actual damages (lost profits plus any profits you earned from the infringement) or elect statutory damages instead. Statutory damages run from $750 to $30,000 per work infringed, at the court’s discretion.10Office of the Law Revision Counsel. 17 U.S. Code 504 – Remedies for Infringement: Damages and Profits
State of mind shifts those numbers dramatically. Willful infringement can push statutory damages as high as $150,000 per work. If you can prove you genuinely had no reason to believe your use was infringing, the floor drops to $200 per work.10Office of the Law Revision Counsel. 17 U.S. Code 504 – Remedies for Infringement: Damages and Profits Courts also have discretion to award attorney fees to the prevailing party.11Office of the Law Revision Counsel. 17 U.S. Code 505 – Remedies for Infringement: Costs and Attorney Fees
One catch matters for anyone thinking about their exposure: statutory damages and attorney fees are only available if the copyright holder registered the work before the infringement began, or within three months of first publication.12Office of the Law Revision Counsel. 17 U.S. Code 412 – Registration as Prerequisite to Certain Remedies for Infringement Without timely registration, the copyright holder is limited to actual damages.
The Open Question: AI Training
Whether training a generative AI model on copyrighted works qualifies as fair use is the largest unresolved question in the doctrine right now. The U.S. Copyright Office published Part 3 of its Copyright and Artificial Intelligence report on this topic but declined to offer a definitive rule, providing an analytical framework instead.13U.S. Copyright Office. Copyright and Artificial Intelligence, Part 3: Generative AI Training
Two points from the report are worth flagging. The Office rejected the analogy between AI training and human learning, calling it “faulty.” It also said knowingly using pirated or illegally obtained works for training should weigh against fair use, even if it isn’t automatically disqualifying.13U.S. Copyright Office. Copyright and Artificial Intelligence, Part 3: Generative AI Training
Dozens of lawsuits are pending, and trial-level rulings have split. Some judges have found training on lawfully acquired works transformative because the model extracts statistical patterns rather than reading the works for their original purpose. Others have rejected fair use where the AI product competes with the source material. Warhol‘s emphasis on whether the new use serves the same purpose as the original will shape how these cases develop as they reach the appellate courts.