But this rule, as set down in the Skidmore v. Led Zeppelin appeal, has at least one prominent skeptic in Paul Goldstein, a professor at Stanford Law School who is the author of a widely cited copyright treatise.

“Where I disagree with Skidmore,” Goldstein wrote in an email, “is in its assertion that the fact the copyright was secured by deposit of a copy of the musical work implies that the deposit copy defines the scope of copyright in the work to the exclusion of any other relevant evidence.” That evidence, he said, could include things like drafts and correspondence around a song’s creation.