The Telephone as Prior Art to the Electric Guitar?


The 1937 patent prosecution history for the first electric guitar strikes a familiar refrain for today’s IP attorneys, except where prior art claims trace back surprisingly to a 19th century long-distance oral communications invention.

171PatentFig1-3The electric guitar—the transmuted iconic American instrument that in turn helped transform FryingPan_fulljazz and blues music and later propel the rise of rock and roll—was recognized by the United States Patent Office on August 10, 1937 with the issuance to inventor G.D. Beauchamp of Patent #2,089.171 for an electric musical instrument known as the “Rickenbacker Frying Pan”.

What revolutionized the guitar and its importance in popular music was the innovative method for transforming the otherwise gentle sound of an acoustic guitar string into an electrical signal that could be amplified and re-converted back into audible sound at a much greater volume. A truly novel, non-obvious invention, yes? Not in the opinion of the US Patent Office.

FryingPan_MCUWhen a vibrating string is placed within a magnetic field, it is possible to “pick up” the sound waves created by thatBellPhone_Pix string’s vibrations and convert those waves into electric current. However, substitute the word “string” with the word “membrane” in that statement, and you also have a description of                                                                      how a telephone works.

With Alexander Bell’s 1876 patented “Telegraphy” identified as prior art, Beauchamp’s patent application had to be revised several times to render the patent claims truly novel and not merely an obvious, variant application of an existing prior invention – the telephone.

Inventor G.D. Beauchamp, partner with Adolph Rickenbacher in the Electro String Instrument Corporation of Los Angeles, California, spent more than five years pursuing his patent on the Frying Pan. Sadly for the Electro String Corporation, Beauchamp’s invention had in the interim been obsolesced by the innovations of his competitors, rendering his 1937 patent an item of greater historical interest than economic value.


The idea of Bell’s telephone as anticipating the invention of the electric guitar may seem at first blush like a discordant pairing to the casual observer. But this vexing patent prosecution anecdote could resonate more as an historical cautionary tale with today’s patent attorney.