Ryan M. Birtwell

Seitel, Inc. engages in the provision of seismic data and geophysical services. Its seismic data library includes both onshore and offshore three-dimensional and two-dimensional data and offshore multi-component data. The company was founded in 1982 and is headquartered in Houston, TX.

ValueAct Capital Management LP (ValueAct Capital) is a SEC-registered investment advisor and hedge fund manager headquartered in San Francisco, California. The firm was founded in 2000 by Jeffrey Ubben, Peter Kamin and George Hamel. They are a subsidiary of ValueAct Holdings II LP, which is owned by Affiliated Managers Group, Inc. (NYSE: AMG). ValueAct Capital provides discretionary investment advice and management services to private investment funds and certain other investment vehicles.