The initial court action was triggered in 1919, when Armstrong sued de Forest's company in district court, alleging infringement of patent 1,113,149, and the court ruled in Armstrong's favor on May 17,1921.
The initial court action was triggered in 1919. Armstrong sued de Forest's company in district court. Armstrong was alleging infringement of patent 1,113,149. The court ruled in Armstrong's favor on May 17,1921.