David Sokol, the man considered to be the most likely candidate to succeed Warren Buffett as chief of Berkshire Hathaway, has unexpectedly resigned.
He had found himself at the centre of controversy after purchasing shares in Lubrizol, which was later acquired by Berkshire Hathaway, the Guardian reports.
However, Buffett has denied the purchase had anything to do with the resignation and says Sokol had told him he owned shares in the chemical company when they first discussed the deal in January.
In a statement, he adds neither of them felt "his Lubrizol purchases were in any way unlawful".
In the middle of March, Berkshire announced the $9bn (£5.6bn) takeover of Lubrizol, while Sokol bought nearly $10m of shares in the company before the acquisition.
In his resignation letter to Buffett, Sokol says: "As I have mentioned to you in the past, it is my goal to utilise the time remaining in my career to invest my family's resources in such a way as to create enduring equity value and hopefully an enterprise which will provide opportunity for my descendants and funding for my philanthropic interests."
Sokol had been with Berkshire Hathaway since 1999 and had run a number of the company's subsidiaries.
Outlook for income
Chris St John to take over £3bn UK Select Opps