Guglielmo Marconi was an Italian inventor, known for his pioneering work on long distance radio transmission and for his development of Marconi's law and a radio telegraph system. Marconi is often credited as the inventor of radio, and he shared the 1909 Nobel Prize in Physics with Karl Ferdinand Braun "in recognition of their contributions to the development of wireless telegraphy."

Marconi claimed he invented it and as a result even shared the 1909 Nobel Prize in Physics. The media at the time - and thus popular opinion - embraced his claims. But in 1943, only months after his death, the United States Supreme Court finally gave inventor Nikola Tesla recognition as the first to truly conceive of and patent the principles of radio (or what he called 'World Telegraphy'). They struck down Marconi's fundamental patent.

The truth was that Tesla originally filed his own basic radio patent applications in September of 1897 and they were granted on March 20, 1900. Marconi's first patent application in the US was filed well after that, on November 10, 1900. He was turned down. Marconi's revised applications over the next three years were repeatedly rejected because of the priority of Tesla and other inventors.

In 1903, the US Patent Office commented: "Many of the claims are not patentable over Tesla patent numbers 645,576 and 649,621, of record, the amendment to overcome said references as well as Marconi's pretended ignorance of the nature of a 'Tesla oscillator' being little short of absurd ... the term 'Tesla oscillator' has become a household word on both continents [Europe and North America]."