Warren Buffett is now the longest-tenured CEO in the S&P 500 following Les Wexner's exit from L Brands

• On Thursday, Les Wexner, the longtime CEO and founder of Victoria's Secret parent company L Brands, announced he will step down.
• Wexner was the longest-tenured CEO in the S&P 500, having served 57 years at L Brands.
• After Wexner's exit, Warren Buffett is now the longest-tenured CEO in the S&P 500. He's led Berkshire Hathaway for 50 years.
• Here's a list of other long-serving S&P 500 CEOs, according to The Conference Board.
• Read more on Business Insider.

Warren Buffett, the leader of Berkshire Hathaway, famed value investor, fourth-wealthiest person in the world, and the "Oracle of Omaha," can add one more title to his list: longest-tenured S&P 500 CEO.

Buffett, 89, who has been at the head of Berkshire Hathaway for 50 years, gained the title Thursday when Les Wexner, 82, announced he would step down as the CEO of Victoria's Secret parent company L Brands after 57 years.

Wexner's departure from the company he founded in 1963 comes after years of struggle at Victoria's Secret, as the brand failed to stay relevant in an ever-changing retail landscape.

On Thursday, L Brands announced that private equity firm Sycamore Partners will acquire a 55% stake in the Victoria's Secret brand, valued at $1.1 billion. Wexner will stay on the board of directors as chairman emeritus and Andrew Meslow, the current chief operating officer of Bath & Body Works, also owned by L Brands, will take over as CEO.

Wexner's personal ties to disgraced financier Jeffrey Epstein also added to mounting pressure surrounding his eventual resignation. Epstein previously managed Wexner's money, and the two reportedly had a close relationship. Epstein died by an apparent suicide in August while facing charges of conspiracy and the sex trafficking of minors.

Buffett has been the CEO of Berkshire Hathaway since 1970, and has run the company alongside his investing partner Charlie Munger, 96, since 1978. While Buffett hasn't formally announced a succession plan, he highlighted the work of two key Berkshire Hathaway executives - Greg Abel and Ajit Jain - in his 2018 annual shareholder letter.

"Berkshire is now far better managed than when I alone was supervising operations. Ajit and Greg have rare talents, and Berkshire blood flows through their veins," Buffett wrote.

Here's what the list of longest-tenured S&P 500 CEOs and how long they've held the job will look like when Wexner is officially out at L Brands, according data from The Conference Board.

1. Warren Buffett, Berkshire Hathaway, 50 years.
2. Alan B. Miller, Universal Health Services, 42 years.
3. James Herbert, First Republic Bank, 34 years.
4. Harold Max Messmer, Jr., Robert Half, 32 years.
5. Richard Fain, Royal Caribbean Cruises, 31 years.
6. Leonard Schleifer, Regeneron Pharmaceuticals, 31 years.