Complex sentence: In 1997, Mr. Roscheisen co-founded TradingDynamics, an enterprise software company acquired by Ariba in Nov 1999 for $740 million; and, in 1998, Mr. Roscheisen became CEO of eGroups, an email messaging company acquired by Yahoo in September 2000 for $450 million.
Split into simpler sentences: In 1997, Mr. Roscheisen co-founded TradingDynamics, an enterprise software company acquired by Ariba in Nov 1999 for $740 million. In 1998, Mr. Roscheisen became CEO of eGroups, an email messaging company acquired by Yahoo in September 2000 for $450 million.