David Morgenthaler, who founded venture capital firm Morgenthaler Ventures in 1968, died in Cleveland on Friday. He was 96.

A cause of death is not immediately available.

Morgenthaler was a founding director, president, and chairman of the National Venture Capital Association (NVCA), according to Morgenthaler Ventures. He helped lower capital gains tax rates from 49 percent to 28 percent in 1978, the firm said. He also helped bring about changes to the “Prudent Man Rule” of the Employee Retirement Income Security Act (ERISA) in 1979.

“With those two changes, venture capital went, in 1977, ’78, from one to two hundred million dollars in capital a year, to two and then four billion dollars of capital within the next three to four years,” David Morgenthaler’s son Gary Morgenthaler, who is still a partner at Morgenthaler Ventures, said in an 2005 oral history he did with the Computer History Museum. “They realized a 20 times increase in the amount of capital available to form their companies. That is the story that’s built Silicon Valley, that I believe is not understood by people.”

Morgenthaler Ventures was established in Cleveland, not in Silicon Valley. Today it has offices in Cleveland, Boston, and California’s Portola Valley. It invests in IT and life sciences companies and also does private equity deals.

The firm has raised some $3 billion over the years and most recently raised the $175 million Canvas Venture Fund in 2013. The firm’s investments include Apple, Nuance, and Siri. Current portfolio companies include Convo, Doximity, Evernote, MuleSoft, and Socrata.

David Morgenthaler was born on August 5, 1919, in South Carolina. He graduated with bachelor’s degrees from the Massachusetts Institute of Technology in 1941 and later served in the U.S. Army Corps of Engineers.

Later in his life he donated money to Carnegie Mellon University, the Cleveland Clinic, MIT, and Stanford University.

He is survived by his wife, Lindsay Jordan Morgenthaler, as well as three children, seven grandchildren, and four great-grandchildren.