Complex sentence: 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.
Split into simpler sentences: 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. The court ruled in Armstrong's favor on May 17,1921.