Sheets v. Selden's Lessee was a case heard by the United States Supreme Court in 1864. The dispute centered around whether or not an individual could obtain a copyright for a book that contained instructions on how to use and construct accounting systems, which included blank forms of accounts. The plaintiff argued that he had created such a system and should be granted exclusive rights to it under the Copyright Act of 1790, while the defendant argued that since they were only using parts of his work, they did not need permission from him nor should he receive any compensation for their usage. After much deliberation, the court ultimately ruled in favor of the defendant; stating that although some elements may have been taken from Sheets' work without his consent or payment, these elements were merely "incidental" components used within another larger copyrighted work - thus making them exempt from copyright protection as per Section 8 of the Copyright Act.

In Sheets v. Selden's Lessee, the Supreme Court was asked to decide whether a copyright of a book on double-entry bookkeeping could be extended to include an accounting system based upon that same method. The majority opinion held that the copyright did not extend beyond the literal text of the book and thus rejected plaintiff's claim for infringement. However, in his dissenting opinion Justice Grier argued that while it is true that copyrights do not protect ideas or systems, they can extend to expressions of those ideas or systems if they are sufficiently original and creative works. He further stated that since there was evidence presented at trial showing substantial similarity between defendant’s work and plaintiff’s copyrighted material, he would have found in favor of plaintiff as this constituted sufficient proof of infringement under existing law.