Warren Buffett has raised nearly $30 million for this charity — here's why

Warren Buffett explains how his late wife convinced him to raise money for...

Warren Buffett spent his 88th birthday sharing a swanky meal — complete with sirloin steak, hash browns and an extravagant Coca-Cola-themed cake — and likely some of his best life lessons with the winner of the 18th annual charity luncheon benefiting the Glide Foundation on Thursday.

The billionaire investor started the annual tradition of donating his time to support his late wife Susan's passion for social justice and, throughout the past 18 years, Buffett has raised nearly $30 million for Glide, an anti-poverty non-profit organization based in San Francisco. Co-founders Cecil Williams and Janice Mirikitani tell CNBC Make It that the lunch auction was originally Susan's idea.

"We met Susie 25 years ago, but she had actually been coming to Glide for nearly two years before that. She wanted to make sure we were not a cult," Mirikitani says with a laugh. "When she saw we advocated for inclusiveness and social justice for everyone, she started to volunteer."

When they were in their 30s, Susan inspired Warren to support social issues. "When the children were growing up, I was very involved in civil rights. I was immersed in it and I think that's what made Warren a Democrat. He would go with me to hear speakers," Susan says in the HBO documentary "Becoming Warren Buffett."

Together they supported Omaha's nonviolent activists in the midst of the civil rights movement during the 1950s and 1960s, as well as late civil rights activist and icon Martin Luther King Jr.

In the 1990s, Susan traveled with Williams and Mirikitani four-to-five times a year, for three years, going to different American cities to train other churches on how to start programs similar to the ones Glide offered.

But when Warren first heard about Glide, he was skeptical.

"My wife told me a lot about Cecil and I thought, 'This sounds too good to be true,' and I am a suspicious guy by nature," Buffett tells CNBC reporter Becky Quick in a 2017 interview. "So she didn't sell me."

Susie Buffett volunteering during GLIDE’s free Grocery Bag Giveaway during the holidays.
Photo courtesy of the Glide Foundation

Buffett looked for, and found, the proof he needed. "But then she took me there one time to Glide and I got to meet Cecil, I got to see what happened, the kind of people he was helping and how he was helping them."

At that point, Mirikitani recalls, "Warren looked at Cecil and said 'This guy is real!'"

Glide expanded its budget from $35,000 in 1965 to $20 million today, Mirikitani says. Buffett does not personally donate anything, except for his time, to Glide, CNBC Make It confirms.

To this day, Glide, which doubles as a church, helps fulfill the basic needs of marginalized people by providing more than 770,000 meals, affordable health care, mental health services, substance abuse recovery programs and HIV and AIDS prevention programs, among other services.

Susie Buffett volunteering during GLIDE’s free Grocery Bag Giveaway during the holidays.
Photo courtesy of the Glide Foundation

In 2000, Susan came up with the million-dollar lunch auction idea, which Williams and Mirikitani say they happily welcomed. But they struggled to raise anything more than $25,000 during the in-person public auctions in San Francisco until 2003, when Warren proposed running the auction on eBay. By 2008, the auction had a $2 million-bidder for lunch with Warren.

Though Susan passed away in 2004, Williams and Mirikitani say they still chat with Buffett several times a year. They say they are still in awe of how humble the investor is about his impact and how willing he is to work closely with them.

"We can't overlook the fact that he's helping to raise millions of dollars for Glide, but the development of our friendship with Warren has been one of the best parts of this partnership," Mirikitani says.

Rev Cecil Williams, Warren Buffett and GLIDE Co-founder Janice Mirikitani (Rev. Williams’ wife).
Photo by Thomas Walsh

Mirikitani adds that "Warren credits Susan for having really caused him to understand the meaning of unconditional love," a value embedded in Glide's mission.

Buffett also thanks Susan for much of his success in life, calling her one of his "greatest teachers" in a 2017 Forbes interview.

"Who you marry, which is the ultimate partnership, is enormously important in determining the happiness in your life and your success and I was lucky in that respect," Buffett says.

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