All that glitters is not gold: Last year, Michael Skidmore, as trustee for the Randy Craig Wolfe Trust, brought claims in the U.S. District Court for the Eastern District of Pennsylvania against the living members of the band Led Zeppelin and various music industry companies associated with Led Zeppelin for direct, contributory, and vicarious copyright infringement. The Plaintiff claims that the opening of Led Zeppelin's 1971 song "Stairway to Heaven" sounds substantially similar to the instrumental song "Taurus," which was recorded by the band, Spirit, in 1968. On May 6 of this year, the Defendants' Motion to Dismiss was denied, and the suit was transferred to the U.S. District Court for the Central District of California, Western Division, where it is being considered.

Are the Plaintiff's thoughts misgiven? Many listeners are convinced that Led Zeppelin copied the opening of "Stairway to Heaven" directly from Spirit's "Taurus." Others listeners believe the two works merely share certain musical elements and the chord progression in "Taurus" is not protectable by copyright law. Further, the two bands toured together in the early 70s, so there is no doubt that members of Zeppelin were exposed to the song. But is it enough to win a copyright infringement suit?

The piper will lead us to reason: To determine infringement, courts have relied on the following two-prong test: (i) copying of a prior work; and (ii) a substantially similarity to the prior work sufficient to constitute improper appropriation. Copying can be proven by circumstantial evidence, where courts will typically consider the amount of access and similarity to determine whether copying took place. Second, for evidence of substantially similarity of prior work, courts will likely consider expert witness testimony from both parties.

If there's a bustle in your hedgerow, don't be alarmed now: The vast majority of copyright infringement suits settle outside of court to avoid spending time, money and resources, as well as exposure to the possibility of an adverse jury verdict. The parties will likely reach an agreement involving a monetary payment to Spirit, and may even grant credit to guitarist Randy California for the "Stairway" opening. That is how Led Zeppelin resolved prior claims of copyright infringement brought by third party artists regarding other Led Zeppelin songs including "Whole Lotta Love," "Babe I'm Gonna Leave You," "The Lemon Song," and "Dazed and Confused."

Take the challenge: Listen to both songs.

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