US billionaire financier Thomas Lee found dead at 78

American financier Thomas Lee, a pioneer in private equity, has died at the age of 78, his family has confirmed.

“The family is extremely saddened by Tom’s death,” family friend and spokesperson, Michael Sitrick said in a statement. “While the world knew him as one of the pioneers in the private equity business and a successful businessman, we knew him as a devoted husband, father, grandfather, sibling, friend and philanthropist who always put others’ needs before his own. Our hearts are broken. We ask that our privacy be respected and that we be allowed to grieve.”

The NYPD told the BBC that an unidentified 78-year-old man had been found dead at 767 Fifth Avenue – the address listed for Thomas H Lee Capital LLC. A police spokesperson said the cause of death will be determined by a medical examiner.

Police added that they responded to a 911 call just after 11am on Thursday at the Fifth Avenue office.

“Upon arrival EMS responded and pronounced the male deceased at the scene,” the authorities said, according to the BBC.

When he died, Mr Lee was estimated to be worth $2bn, according to Forbes.

He pioneered the use of the leveraged buyout – when one company acquires another using large amounts of borrowed money – and became known for buying beverage firm Snapple in 1992 for $135m and selling it to Quaker Oats two years later for $1.7bn, which was 32 times the amount that he purchased the company for. Quaker Oats soon sold Snapple at a huge loss, only getting $300m for the company.

His previous firm that still holds his name said in a statement that “we are profoundly saddened by the unexpected passing of our good friend and former partner, Thomas H. Lee”.

“Tom was an iconic figure in private equity. He helped pioneer an industry and mentored generations of young professionals who followed in his footsteps,” the firm added.

His firm didn’t get the reputation, as many other private equity firms have, of making massive cuts, such as firing staff, after an acquisition to make it more valuable ahead of selling it, according to CNN.

When he acquired Snapple, he boosted its value before selling it to Quaker Oats by growing the business and increasing sales. The revenue is reported to have spiked from $95m to $750m.

“He’s that rare thing on Wall Street — a genuinely nice guy,” Forbes wrote in a 1997 profile.

He left the firm bearing his name in 2006 to start another one – Lee Equity Partners. The company’s site states that he has invested $15bn over the course of the last 46 years.

He began as an analyst at L.F. Rothschild & Company in its institutional research department.