How do courts decide whether one song copied another?

Song copying disputes run on a different track from sampling. If audio was lifted from a record, the question is clearance, covered on our music sample and copyright clearance page. This page deals with the harder case: two songs sound alike, no audio was taken, and one writer says the other took the melody, the hook or the structure. For music rights more broadly, see our main entertainment law page.

How a song copying claim moves, step by step

1. Pin down what was taken. A song and a recording of it are separate works (Circular 56A), and the Copyright Office names the main elements of a song as melody, rhythm, harmony and lyrics (Compendium 802.3).
2. Confirm who owns the right. Only the legal or beneficial owner of an exclusive right can sue, for infringement committed while it owned that right (17 U.S.C. 501(b)).
3. Register the song. A suit over a U.S. work generally waits for registration or a refusal (section 411(a)). Our page on how to register a song copyright explains the options; online filing costs $45 for a Single Application or $65 for a Standard Application (Copyright Office fees).
4. Choose the forum. Smaller claims can go to the Copyright Claims Board, where recovery is capped at $30,000 per proceeding and the respondent has 60 days from service to opt out (17 U.S.C. 1504(e), 1506(i)).
5. File in federal court. State courts have no jurisdiction over copyright claims (28 U.S.C. 1338(a)). Venue lies where the defendant resides or may be found (28 U.S.C. 1400(a)); for Fulton, DeKalb, Cobb or Gwinnett County, that is the Atlanta Division of the Northern District of Georgia (28 U.S.C. 90). See our page on an IP lawsuit in Atlanta federal court.
6. Serve, answer, demand a jury. Service is due within 90 days of filing (Fed. R. Civ. P. 4(m)), an answer generally within 21 days of service (Rule 12(a)), and a jury demand within 14 days after the last pleading on the issue (Rule 38(b)).
7. Discovery and musicologists. Each side often relies on a musicologist, as both did in Skidmore. Absent a stipulation or order, expert disclosures are due at least 90 days before trial (Rule 26(a)(2)(D)).
8. Decision and remedies. The tests below decide liability; remedies follow sections 502 to 505.

What does a song's owner have to prove?

The Copyright Act gives the owner of a song the exclusive rights to reproduce it, prepare derivative works from it, distribute it and perform it publicly (17 U.S.C. 106), and anyone who violates those rights is an infringer (17 U.S.C. 501(a)). In Skidmore v. Led Zeppelin, the court put the claim in two elements: the owner must show that it owns a valid copyright, and that the defendant copied protected aspects of the work. The second element has two parts, copying and unlawful appropriation, which the court stressed are distinct.

Before any of that, a lawsuit over a United States work generally needs a registration, or a refused application, before it can be filed (17 U.S.C. 411(a)). A certificate issued before or within five years after the song's first publication counts as prima facie evidence that the copyright is valid (17 U.S.C. 410(c)).

How is copying proved without a confession?

Most cases have no direct evidence, so copying is shown circumstantially. The owner points to access, meaning the accused writer had a chance to hear the earlier song, and to similarities that suggest copying rather than coincidence, independent creation or a shared earlier source. At this stage, the court said, similarities in unprotected material can count too.

Independent creation is a complete defense. If two writers truly arrived at the same passage separately, there is no infringement, however close the songs sound. Access is also easier to show than it used to be: the Skidmore court observed that with streaming and on-demand services, access may be established by "a trivial showing" that a work is available.

What counts as substantial similarity?

Copying alone is not enough. The owner must also show unlawful appropriation, meaning the songs are substantially similar in protected expression. In the Ninth Circuit that takes two tests, and both must be met. The extrinsic test compares specific expressive elements objectively, and it requires separating the protected material in the earlier song from the unprotected material. In Skidmore, musicologists for each side gave that analysis. The intrinsic test asks whether an ordinary, reasonable observer, without technical help, would find the expression similar.

Which parts of a song are not protected?

Copyright never extends to "any idea, procedure, process, system, method of operation, concept, principle, or discovery" (17 U.S.C. 102(b)). The Copyright Office adds names, titles and short phrases, listing song titles, slogans and catchphrases among its examples (Circular 33). A shared title or a short common phrase, standing alone, is therefore a weak basis for a claim.

For music, the Office's manual treats diatonic or chromatic scales, arpeggios and chord symbols based on standard chord progressions as common property material (Compendium, section 802.5(A)). Short musical phrases lack enough authorship to be protected (section 802.5(B)). Its own example of an unregistrable harmonization is the four-chord sequence C, A minor, D minor, G, which it calls both standard and too short (section 802.6(C)(1)).

In Skidmore, the court upheld a jury instruction that copyright does not protect ideas, themes or common musical elements, such as descending chromatic scales, arpeggios or short sequences of three notes, and it noted that it had never extended protection to just a few notes. A combination of unprotected elements can still be protected, but only if the elements are numerous enough and their selection and arrangement original enough to make an original work. A list of scattered similarities is not the same thing.

What did the court decide in Skidmore v. Led Zeppelin?

The trustee for the writer of Taurus, an instrumental recorded by the band Spirit, claimed that the opening of Stairway to Heaven copied it. A jury found that the songs were not substantially similar, and on March 9, 2020 the en banc Ninth Circuit affirmed. Three holdings matter to songwriters:

• The 1909 Copyright Act governed, because Taurus was registered in 1967 as an unpublished composition, and the deposit copy filed with that registration defined the scope of the copyright. Here that was one page of sheet music, so the jury did not compare recordings of Taurus with their added embellishments. The court also noted that recordings have been accepted as deposit copies for decades.
• The court rejected the inverse ratio rule, which had allowed a lower standard of proof of similarity when access was strong, and overruled its earlier cases. Access can be circumstantial evidence of copying, the court said, but it cannot prove substantial similarity.
• Leaving out a selection and arrangement instruction was not an error, because the plaintiff never presented that theory at trial.

Does Skidmore apply to a case in Georgia?

Skidmore binds federal courts in the Ninth Circuit. Federal cases from Georgia go to the Eleventh Circuit, which hears appeals from Alabama, Florida and Georgia (U.S. Court of Appeals for the Eleventh Circuit), so a song case filed in Atlanta follows Eleventh Circuit precedent. Our page for Atlanta IP and entertainment clients covers which court hears a local case.

Is copying a recording different from copying a song?

Yes. The copyright in a sound recording covers its actual sounds. The owner's reproduction right is limited to duplicating those sounds, and the derivative right to rearranging, remixing or otherwise altering them; neither reaches a new recording made entirely of independently recorded sounds, even if it imitates or simulates the original (17 U.S.C. 114(b)). A soundalike re-record does not infringe the master, but it still uses the song underneath, which needs its own permission. Our guide to legally clearing a music sample covers both paths. Our page on the cover song license explains how recording someone else's song works.

What changes the answer

• Composition or recording. A song claim asks whether protected musical expression was copied; a master claim asks whether the actual sounds were duplicated (17 U.S.C. 114(b)).
• What the shared material is. Common property material (Compendium 802.5) adds little; an original melody or original combination is far stronger.
• Older registrations. For a song registered unpublished under the 1909 Act, Skidmore held that the deposit copy defines what is protected.
• When the song was registered. Late registration can rule out statutory damages and fees (17 U.S.C. 412), as our page on copyright infringement damages explains, and can weaken the certificate's weight (410(c)).
• When the claim is brought. A civil action must start within three years after the claim accrued (17 U.S.C. 507(b)).

A worked example

Common mistakes

• Building the claim on a shared title or short hook phrase, which the Copyright Office treats as unprotected (Circular 33; Compendium 802.5(B)).
• Counting a common chord progression, scale run or arpeggio as copying.
• Comparing two finished recordings when the claim is about the composition.
• Relying on strong access to make up for weak similarity, the inverse ratio rule Skidmore rejected.
• Deleting drafts or session files after an accusation, when they may prove independent creation.

What to do this week

1. Write down exactly what is claimed: composition, recording or both, and which bars or lines.
2. Back up every dated draft, voice memo and session file, unedited.
3. Check whether the song is registered and who is named as claimant; if not, file now.
4. Confirm the writers, splits and publishing deals; our post on music copyright ownership disputes shows how unsettled splits can block a claim.
5. List the key dates: your release, the other song's release, and when you first heard it.
6. If a demand letter arrived, read our guide for when you have received a copyright infringement letter before replying.

Frequently asked questions

Can a chord progression be copyrighted?

Not a standard one. The Copyright Office lists chord symbols based on standard chord progressions as common property material (Compendium 802.5(A)), and calls C, A minor, D minor, G too standard and too short to register (802.6(C)(1)).

How many notes does it take to infringe?

There is no fixed number. The Copyright Office says no predetermined number of notes decides the question, though a phrase of a few notes is too short (Compendium 802.5(B)), and Skidmore noted the Ninth Circuit had never protected just a few notes.

Can you sue in a Georgia state court over a copied song?

No. No state court has jurisdiction over a claim arising under the copyright laws (28 U.S.C. 1338(a)), so a Georgia case goes to federal district court, with appeals to the Eleventh Circuit.

Do older songs follow different rules?

Sometimes. Whether an older song is still protected at all is covered on our page on how long a song copyright lasts. Recordings made before 1972 follow their own federal rules, explained on our page on pre-1972 sound recordings protection.

Does an interpolation need permission even if no audio is sampled?

Usually, yes. Re-recording part of someone else's melody or lyric does not copy their master (17 U.S.C. 114(b)), but it does use their composition, which generally needs the song owners' permission.

What if the song was copied by a business, not another songwriter?

The same rules apply, often to an advertisement or video using a soundalike track. Such disputes frequently start with a letter, and our post on cease and desist letters explains that first step.

Zala IP Law advises songwriters, artists, producers and publishers on infringement response and clearance, and Shreepal J. Zala performed professionally as a guitarist before law school. If you have received a claim, or believe your song was taken, request a consultation or call 404-313-1701.