Christian E. Callsen

The Optima Corp. Ltd. develops mathematically based software solutions. Its services include demand analysis, resource modeling, base location planning, resource analysis, post plan building, and detailed data analysis. The company was founded by Andrew James Mason, David Murray Ryan, Paul Rodger Day and Jeff A. Meyer in 1998 and is headquartered in Auckland, New Zealand.

Envision Healthcare Corp. provides physician-led, outsourced medical services. It provides a broad range of coordinated, clinically-based care solutions across the continuum of care, from medical transportation to hospital encounters to comprehensive population health services. The firm solutions include healthcare system payers, community and government leaders, clinicians, improving patient experiences, improving clinical outcomes, reducing cost of care, improving provider experiences, and population health. The company was founded on November 1, 2005 and is headquartered in Greenwood Village, CO.