Complex sentence: In 1901 DeForest fell into competition with Guglielmo Marconi at the New York's International Yacht Races, each working for rival news services, and using their own inventions.
Split into simpler sentences: In 1901 DeForest fell into competition with Guglielmo Marconi at the New York's International Yacht Races. Both working for rival news services and using their own inventions.