Financier Nat Rothschild, co-founder of coal miner Bumi, was defeated in his bid to oust the company's current chairman and chief executive on Thursday, losing a public showdown with Indonesia's influential Bakrie family.
Rothschild had wanted to oust 12 of 14 board members, bring in his own team and join the board himself.
Shareholders rejected Rothschild's attempt to rejoin the board and also opted to keep the current top management, voting against his proposed replacements.
Earlier, the current board said it has already agreed a split with the Bakries - something all sides agree is critical - in a deal that would be jeopardized if Rothschild returned to the board.
"Is there a future for this company? We have all heard a lot of doom and gloom, we have heard a lot of noise. Absolutely there is a future," non-executive director and former diplomat Robin Renwick told shareholders.
He predicted a share rise, "provided we execute the separation, provided we get the cash to develop Berau, and subject to there being an uptick in the thermal coal price".
Rothschild's campaign was damaged by a last-minute stake sale by a major Indonesian investor earlier this week, freeing up shares whose voting rights had been frozen by regulators.
"It is not personal at all. I only have one aim - and I have around 36 million shares in this company, together with my cousin - I want the share price to appreciate," Rothschild said as investors gathered to vote, flanked by his mother in a show of support from the banking dynasty.
He says there has already been increase in interest in minority shareholders as a result of his intervention. But his campaign - punctuated by lengthy press releases and full-page newspaper adverts - means a defeat will almost certainly be perceived by many investors as a personal loss.
Rothschild, the 41-year-old hedge fund veteran known for his bulging contact book, set up Bumi with Indonesia's politically connected influential Bakrie family.
"To me, this idea of an Indonesian company married to an English (board) had the makings of a brilliant success," said one small shareholder, pensioner Michael Napier.
But the partnership, intended in 2010 to bring promising Indonesian assets to London investors and to unlock value by applying UK governance rules, soured within months, and the two sides have been locked in a bitter battle since.
Tensions between Rothschild and his Indonesian partners came to a head last year, after Bumi announced an independent investigation into potential wrongdoing at its Indonesian subsidiaries. Weeks later, the Bakries said they wanted to draw a line under the London adventure and pull out their assets.
'We May Not Win'
Before the vote, Rothschild told CNBC on Thursday that shareholders in the company were unlikely to vote in all of the representatives he has put forward as new board members.
"It's highly unlikely... that we will succeed in getting all of our representatives onto the board," Rothschild said. "I think the result today...is one of the most overwhelming protest votes that the U.K. has ever seen and the board of this company genuinely lacks a mandate to continue in its current form."
"It may be difficult for us to win," he said.