# Climbing Down: Skidmore v. Led Zeppelin and the End of the Inverse Ratio Rule

> The en banc Ninth Circuit's decision upholding the 'Stairway to Heaven' verdict, confining old compositions to their deposit copies, and abolishing the inverse ratio rule.

Topic: Copyright  |  Author: Lidiia Levitska  |  Source: Intellectual Property Law (outsideipcounsel.com)
Canonical: https://outsideipcounsel.com/blog/skidmore-v-led-zeppelin-stairway-substantial-similarity/


*Skidmore v. Led Zeppelin*, Nos. 16-56057 & 16-56287 (9th Cir. Mar. 9, 2020) (en banc), is the rare music copyright decision that reshaped doctrine while reaching a result the public found anticlimactic: Led Zeppelin won, again. The trustee for the late Randy Wolfe ("Randy California" of the band Spirit) claimed that the opening of "Stairway to Heaven" (1971) infringed Spirit's instrumental "Taurus" (1967). A jury had said no. The en banc Ninth Circuit affirmed, and in doing so confined older compositions to their Copyright Office deposit copies, reaffirmed the limits of "thin" protection for common musical building blocks, and abolished the long-criticized "inverse ratio rule."

## At a glance

- **Matter:** *Skidmore v. Led Zeppelin*, Nos. 16-56057 & 16-56287 (en banc)
- **Forum:** U.S. Court of Appeals for the Ninth Circuit, sitting en banc (on appeal from the Central District of California, Judge R. Gary Klausner)
- **Decided:** March 9, 2020 (Supreme Court denied certiorari later in 2020)
- **The works:** Spirit's "Taurus" (registered 1967) and Led Zeppelin's "Stairway to Heaven" (1971)
- **The disputed material:** A descending chromatic bass line under an A-minor chord, a centuries-old musical commonplace
- **Holdings:** The 1909 Act governs; the copyright is limited to the deposit copy (a one-page lead sheet); the inverse ratio rule is abolished; the "selection and arrangement" theory was properly handled
- **Result:** Jury verdict of non-infringement affirmed

## Why the recording never reached the jury

The most consequential ruling is also the most technical. Because "Taurus" was registered in 1967, the 1909 Copyright Act governs the scope of its protection, and under that Act, the protected work is what the author deposited with the Copyright Office. For "Taurus," the deposit was a single-page lead sheet containing the basic notation, not the lush studio recording listeners associate with the song. The 1909 Act did not even extend federal copyright to sound recordings.

That meant the jury could not be played the "Taurus" recording as proof of substantial similarity. Skidmore argued this was reversible error: the recording captured the true expression and the jury should hear how alike the songs sound. The en banc court disagreed: the deposit copy defines the protectable composition for a 1909-Act work, so the comparison must run between "Stairway" and the lead sheet, not the master. The recording could be relevant to other issues, such as access, but not to the similarity of the protected composition itself. This holding gives defendants litigating vintage songs a powerful structural argument: strip the case down to the often-sparse notation on file.

## Thin protection for common building blocks

The substance of the dispute was a descending chromatic line (notes moving down by half-steps) played beneath a minor chord. Skidmore's expert characterized it as a distinctive, protectable sequence; Led Zeppelin's experts called it one of the oldest tricks in Western music, found in works from Bach to countless pop songs. The en banc court did not have to resolve the musicology because the jury, properly instructed, had already found the works not substantially similar. But the opinion reinforced a foundational principle: individual musical elements (a scale, a common chord progression, a chromatic descent) are building blocks in the public domain, and copyright protects only an author's original *selection, coordination, and arrangement* of such elements.

On appeal Skidmore pressed exactly that selection-and-arrangement theory, arguing that even if each element was unprotectable, "Taurus" combined them in an original way. The court accepted the theory's legitimacy but rejected the challenge on three independent grounds. Skidmore had proposed a selection-and-arrangement instruction but never objected when the district court left it out, so the objection was forfeited and reviewed only for plain error, and there was none. Beyond that, the court held there was no error at all because Skidmore never actually presented the theory to the jury: he "never once used the words 'selection' or 'arrangement' during trial" and argued a garden-variety substantial-similarity case built on five component elements rather than on how those elements were arranged into an overall design. Finally, the instructions that were given fairly and adequately covered his extrinsic-similarity argument.

A caution about how the case is often summarized. The majority expressly declined to adopt a heightened "virtual identity" test for selection-and-arrangement claims, stating that it did "not recognize a separate, heightened standard for proving actionable copying" and that "[t]he standard is always substantial similarity." What varies is the degree of overlap needed: where the range of protectable expression is narrow, a defendant's work would have to be virtually identical to be substantially similar, a result the court has "at times described" as a "thin" copyright. The majority added that a selection and arrangement copyright "is not always thin." It was Judge Watford, concurring, who would have applied virtual identity as a separate and more demanding standard here.

## Burying the inverse ratio rule

The en banc court used the case to abolish a doctrine that had distorted Ninth Circuit infringement analysis for decades: the inverse ratio rule, which held that a *strong* showing of access to the plaintiff's work *lowered* the standard of proof for substantial similarity. The logic had always been shaky: access and similarity are conceptually distinct, and the rule effectively let a plaintiff prove less about the actual works by proving more about exposure.

The court catalogued the rule's incoherence and inconsistent application, noted that most circuits had rejected it, and overruled its own precedents endorsing it. Access, the court explained, is a proxy for the factual question of copying; it cannot substitute for the legal question whether enough protectable expression was actually taken to make the works substantially similar. In the streaming era, where virtually any song is universally accessible, the rule had become especially perverse: ubiquity would automatically dilute the similarity required. Eliminating it tightens the analysis and benefits defendants facing claims built on fame and exposure rather than genuine resemblance.

## Open questions

- **Does the deposit-copy rule unfairly shrink old songs?** Composers of the 1909-Act era often deposited skeletal lead sheets; tying protection to that notation may understate the creativity actually fixed in the recording. The fairness of that bargain remains debated.
- **How thin is too thin?** The line between an unprotectable commonplace and an original arrangement of commonplaces is irreducibly fact-bound, leaving substantial uncertainty for both plaintiffs and defendants.
- **Will other circuits formally follow on the inverse ratio rule?** The Ninth Circuit's abolition aligns it with the majority view, but the doctrine's residue lingers in older cases and jury instincts about access.
- **What is the role of expert musicology now?** With recordings excluded for 1909-Act compositions, the battle turns on competing expert readings of sparse notation, an arena prone to advocacy dressed as analysis.

## Implications

- **For vintage compositions, the deposit copy is the case.** Litigants must obtain and scrutinize the Copyright Office deposit; the famous recording may be legally irrelevant to similarity.
- **Building blocks stay free.** Scales, common progressions, and chromatic lines remain unprotectable; only an original selection and arrangement of them qualifies, and the narrower the range of expression, the closer the copying must be before it is actionable.
- **Fame no longer lowers the bar.** With the inverse ratio rule gone, plaintiffs cannot leverage a defendant's exposure to ease their similarity burden.
- **Defendants gain structural tools.** Confining the comparison to the notation on file, and arguing that a narrow range of creative choices demands a closer match, are now potent defenses in song-similarity suits.
- **The Ninth Circuit signaled restraint.** Read alongside the "Blurred Lines" anxiety, *Skidmore* pushes back against expansive music copyright claims built on feel or fame.

## Frequently asked questions

**Why couldn't the jury hear the "Taurus" recording?**
Because "Taurus" is governed by the 1909 Copyright Act, its protected work is the composition as deposited with the Copyright Office, a one-page lead sheet. The 1909 Act did not protect sound recordings, so the comparison for substantial similarity ran between "Stairway to Heaven" and the notation, not the Spirit master.

**What was the "inverse ratio rule" and why did the court abolish it?**
It held that stronger evidence of access to the plaintiff's work lowered the degree of similarity a plaintiff had to prove. The en banc court found the rule logically unsound and unevenly applied (access and similarity are distinct) and overruled it, especially given that in the digital age nearly every work is widely accessible.

**Does Skidmore mean common musical phrases can never be protected?**
Individual commonplaces (a chromatic descent, a familiar chord progression) are not protectable on their own. But an author's original selection and arrangement of such elements can be. The en banc court declined to impose a separate "virtual identity" test on such claims, holding that the standard is always substantial similarity, and it noted that a selection and arrangement copyright is not always "thin." Where the range of protectable expression is narrow, however, the works must be that much closer before the similarity counts as substantial.

## Authorities and sources

- [Skidmore v. Led Zeppelin, 952 F.3d 1051 (9th Cir. Mar. 9, 2020) (en banc): slip opinion (U.S. Court of Appeals for the Ninth Circuit)](https://cdn.ca9.uscourts.gov/datastore/opinions/2020/03/09/16-56057.pdf)
- [Davis Wright Tremaine: "9th Circuit En Banc Ruling in Favor of Led Zeppelin in the 'Stairway to Heaven' Case"](https://www.dwt.com/blogs/media-law-monitor/2020/10/led-zepplin-stairway-to-heaven-copyright-case)
- [Mitchell Silberberg & Knupp: "Ninth Circuit Rules in Favor of Led Zeppelin, Clarifies Standards for Copyright Infringement"](https://www.msk.com/newsroom-alerts-2774)
- [Harvard Law Review: "Skidmore v. Led Zeppelin" case comment](https://harvardlawreview.org/print/vol-134/skidmore-v-led-zeppelin/)
- [Villanova Law Review: "A Long Climb: Led Zeppelin's Stairway to Heaven Prevails in Copyright Lawsuit"](https://www.villanovalawreview.com/post/624-a-long-climb-led-zeppelin-s-stairway-to-heaven-prevails-in-copyright-lawsuit)