RPX received venture funding from Kleiner Perkins Caufield & Byers ( KPCB ) and Charles River Ventures ( CRV ) .
This model was introduced by RPX Corporation , a start - up based in San Francisco .
RPX Corporation received venture funding from Kleiner Perkins Caufield & Byers ( KPCB ) and Charles River Ventures ( CRV ) .
This model was introduced by RPX Corporation , a start - up based in San Francisco .