Piano roll blues
The Piano Roll Blues or Old Piano Roll Blues is a figure of speech designating a legal argument (or the response to that argument) made in US patent law relating to computer software. The argument is that a newly programmed general-purpose digital computer is a “new” machine and, accordingly, properly the subject of a US patent.
This legal argument was made in Gottschalk v. Benson in Benson’s brief. The government then responded in its brief that this amounted to asserting that inserting a new piano roll into an existing player piano converted the old player piano into a new player piano. After Benson, the Court of Customs and Patent Appeals took the position that the reasoning of Benson did not apply to "machine" claims, such as a claim to a conventional digital computer programmed to carry out a new algorithm or computer program. In dissenting from that judgment on the grounds that the Supreme Court in Benson did not limit the principle to method claims, Judge Rich spoke of "the legal doctrine that a new program makes an old general purpose digital computer into a new and different machine." Id. at 773. He observed that the doctrine "partakes of the nature of a legal fiction when it comes to drafting claims." Id.
Yet a player piano playing Chopin's scales does not become a “new machine” when it spins a roll to play Brahms' lullaby. The distinction between the piano before and after different rolls are inserted resides not in the piano's changing quality as a “machine” but only in the changing melodies being played by the one machine. The only invention by the creator of a roll that is new because of its music is the new music.
The expression apparently derives from a song popular in the 1950s—“The Old Piano Roll Blues” by Cy Coben — in the style of a Scott Joplin rag. As Judge Archer points out in his Alappat dissent, there is also an allusion to the decision of the Supreme Court in White-Smith v. Apollo, concerning copyright protection for piano rolls.
- The case most often cited for the argument is In re Bernhart, 417 F.2d 1395, 1400 (CCPA 1969), but a slightly earlier formulation of the argument occurs in In re Prater, 415 F.2d 1393, 1403 n.29 (CCPA 1969).
- For a discussion of the use of the Old Piano Roll Blues in Benson and subsequent cases, see, for example, Chapter 8: Patent Protection of Software: Statutory Subject Matter in the Supreme Court and the Federal Circuit; A. The Supreme Court Trilogy on Statutory Subject Matter, George Washington Law School.
- In re Johnston, 502 F.2d 765 (CCPA 1974), reversed on obviousness grounds sub. nom. Dann v. Johnston, 450 U.S. 175 (1981).
- In re Alappat, 33 F.3d 1526, 1545 (Fed. Cir. 1994) ("We have held that  programming creates a new machine, because a general purpose computer in effect becomes a special purpose computer once it is programmed to perform particular functions pursuant to instructions from program software.").
- Music, Words, Sung (by Al Jolson).