John Gentry, a longtime advertising executive and the chief executive officer of supply-side platform OpenX, died Wednesday evening after a long battle with cancer. He was 58.
A post to Gentry’s LinkedIn profile Thursday evening read: “If you are reading this, it means that I’m no longer around and lost my fight with cancer. While I am dying earlier than most, I outlived myself by 28 years, thanks to a kidney transplant and modern medicine, and I’ve had a wonderful life. I am a lucky and thankful man.”
Gentry went on to express gratitude for the many people he bonded with during the course of his career, saying “the best part of the ride has been all the amazing relationships I’ve formed over the years.”
The company confirmed his death in an email to ADWEEK.
Gentry was considered a trailblazer in adtech, contributing to the innovation of header bidding in the mid-2010s and the evolution of supply-side identity technology.
He was also a thoughtful leader, collaborator, and friend to many.
“JG’s belief in me changed my life,” OpenX president Matt Sattel said in a statement shared with ADWEEK. “He was more than a leader to me. He was an advocate, a mentor, and a friend. JG believed that doing the right thing and building a strong business could go hand in hand, and showed us that it was possible to lead with both strength and humanity, even when it was hard. In challenging moments, he pushed me to think bigger, act with clarity, and put our people first. His career and lessons will stay with me always, and he will be deeply missed.”
A graduate of Northwestern University’s Kellogg School of Management and of UCLA, Gentry worked at the Walt Disney Company in the 1990s, where he directed distribution strategy for ABC cable networks. He went on to hold various executive roles across the advertising and financial services industries, with stints as a senior vice president and general manager at Overture (an early leader in digital advertising acquired by Yahoo for $1.63 billion in 2003), chief revenue officer of financial services company Green Dot, and president of adtech startup Spot Runner—before joining OpenX in 2012.
Gentry was appointed chief executive at OpenX in 2020, after years of serving the company as an advisor, and later, as its president. He steered OpenX through various hurdles, including the disruptive entry of header bidding, evolving privacy regulations, and an ongoing legal battle with Google over antitrust allegations.
