Railway telegraph (continued)
patent interference case
It is erroneously said or implied on several websites that Granville Woods was proven the inventor of the first train telegraph in a court case against either Lucius Phelps or his business partner Thomas Edison. Woods never went head-to-head with Edison himself, but there is indeed a known case where one of Phelps's patent applications, relating to specific improvements of railway telegraphs, was invalidated in a patent office hearing because Woods also had a pending patent on a closely similar idea which he had begun to develop earlier (Phelps subsequently appealed the decision, to no avail). What is not generally known is that Phelps had several other railway telegraph patents — awarded both before and after Woods filed his application on May 21, 1885 — which were not affected, and there had been previous inventors (going back to at least 1873) who patented train telegraph systems years before either Phelps or Edison or Woods applied for patents in this area.
The Woods vs Phelps case is usually made out to be more of a big deal than it actually was. Cases involving interference between patent applications are nothing out of the ordinary, and are initiated by the patent office whenever two or more parties independently submit patent applications covering the same or overlapping ideas. Examiners then sort out who came up with the idea first. Edison and Phelps opposed each other in at least one of these disputes, which they resolved by forming the Consolidated Railway Telegraph Company to pool their interests in train telegraphy.
Interference does not mean anyone "stole" or dishonestly claimed another's invention, even though one side may accuse the other of doing so, as when Phelps accused Woods of getting his ideas from a Scientific American article which described the Phelps railway telegraph and which was published exactly three months before Woods applied for his first railway telegraph patent. Woods was able to prove that he came up with his own plan independently.