Charles T. Munger, vice chairman of Berkshire Hathaway and Warren Buffett’s not-so-silent righthand man, died on Tuesday at the age of 99, reports an obituary in The New York Times. Though Buffett was the more famous of the two, Munger was integral to Berkshire’s success and was a billionaire in his own right, with a fortune of $2.6 billion, according to Forbes Magazine.

Though Buffett started out buying struggling businesses at bargain prices in the 1950s, it was Munger who told him to “buy wonderful businesses at fair prices,” Buffett wrote to his shareholders in an annual report. That strategy was the foundation of Berkshire’s enormous success. Today, the company owns companies in a wide variety of industries, from Geico Insurance to Burlington Northern Santa Fe railroad, and has significant positions in banking giants such as American Express and Wells Fargo as well as stakes in Coca-Cola and IBM. Buffett and Munger’s 50-year partnership was built on mutual respect and admiration; the two talked every day by phone and they held court together at Berkshire’s annual meeting, drawing crowds of thousands

Charles Munger was born on New Year’s Day 1924, and grew up in Omaha, Nebraska. He attended the University of Michigan but left school in his sophomore year to join the Army Air Corps after the attack on Pearl Harbor. He attended Harvard Law School after the war, graduating with honors and beginning his law career in California. After a series of hardships—divorce from his first wife, the death of his 9-year-old son, and financial difficulties—he began to invest, eventually generating millions, the article details. After the death of his father, Munger was in Omaha to organize his estate when he attended a luncheon at the Omaha Club, where he met Warren Buffett. The two formed a fast friendship and began investing together, until Buffett invited Munger to join him as Berkshire’s vice chairman, a position he held for decades as the two men built Berkshire into the $500 billion-plus conglomerate it is today.

Through Berkshire’s success, Munger made far more money than he ever expected, but he spoke often about the mistakes he’d made along the way, like not investing in McDonald’s or Walmart early on, and avoiding the pharmaceutical industry altogether. However, unlike Buffett, he did not pledge to give away at least half of his fortune, because he wanted half of his estate to go to his children, in accordance to his late wife Nancy’s wishes. Munger did have a particular philanthropic passion for architecture, donating hundreds of millions of dollars to university architecture projects, reports The Times. He also gave generously to the Good Samaritan Hospital in Los Angeles, where he maintained a residence; he was also chairman of the board at the hospital for many years. He also served as chairman of the Daily Journal Corporation from 1977 to 2022, among other newspapers that Berkshire invested in.

Two daughters from his first marriage as well as a daughter and three sons from his second marriage survive him, along with two stepsons, 15 grandchildren, and 7 great-grandchildren. Munger was active at Berkshire along with all of his other philanthropic pursuits well into his 90s. When asked by The Times—in an interview for the obituary—if it bothered him to be in Buffett’s shadow, he said, “Ordinarily, everywhere I go I am very dominant, but when somebody else is better, I’m willing to play the second fiddle. It’s just that I was seldom in that position, except with Warren. But I didn’t mind it at all.”