Complex sentence: Philadelphia/Tri State Artists Equity Association, Inc., commonly known as Philadelphia Artists Equity, became an independent organization in 1997, but was originally founded as a chapter of a national organization of professional fine artists in 1949.
Split into simpler sentences: Philadelphia/Tri State Artists Equity Association, Inc., commonly known as Philadelphia Artists Equity, became an independent organization in 1997. It was founded as a chapter of a national organization of professional fine artists in 1949.