Kirk (born March 1, 1954) is an American businessman and investor in pharmaceuticals and biotechnology.
Kirk is the chairman and chief executive officer of Intrexon (NYSE: XON), a biotechnology company.
Kirk started as a lawyer, but is best known for his investments in pharmaceutical and biotech companies.
In addition to high-profile sales of New River Pharmaceuticals, Inc., and Clinical Data, Inc, Kirk also founded investment firm Third Security, LLC, and has held board seats with biotech companies, such as Scios, Inc., and ZIOPHARM Oncology.
He is a billionaire and is listed on the Forbes 400.