Donald K. Grierson
PTC director since 1987. Chief Executive Officer (Retired), ABB Vetco International, an oil services business. Mr. Grierson was Chief Executive Officer and President of ABB Vetco Gray, Inc. from 1991 to March 2001 and from September 2002 to November 2004. Mr. Grierson served as Executive Director of ABB Vetco Gray, Inc. from March 2001 to September 2002.