By Alex MacDonald and Eric Bellman

LONDON--U.K.-listed Indonesian coal miner Bumi PLC (BUMI.LN) said Wednesday its evaluating all its legal and commercial options after receiving the near final version of an independent probe into financial and other irregularities at is Indonesian assets.

It also said that Chief Executive Nalin Rathod will step down at the end of the year but remain a board member. Mr. Rathod, who was appointed Bumi's second CEO in March and has close ties to the powerful Indonesian Barkie family, didn't provide a reason for stepping down.

He will be suceeded by head of corporate affairs Nick von Schirnding, a former senior executive at Anglo American PLC (AAL.LN), who played a key role in the diversified miner's London listing and was a close advisor to Bumi's two successive CEOs. Mr. von Schirnding will join the board at the end of the year.

Bumi's shares have tumbled more than 80% from last year's high after a boardroom rift over corporate governance erupted and an independent probe was launched into financial irregularities at Bumi's 29% owned Indonesian coal miner PT Bumi Resources TBk (BUMI.JK), one of the jewels in the Bakrie family's Bakrie Group conglomerate.

The fraught relations between the company and the powerful Indonesian Bakrie family prompted Bakrie Group to offer an end to relations with the company by buying back all of Bumi's coal assets for $1.2 billion in cash and cancelling its 23.8% stake in Bumi. The proposal, however, met strong opposition from a large group of minority shareholders, led by major shareholder and co-founder Nathaniel Rothschild. The minority shareholders group said it would block the Bakrie Group offer in favor of their own proposal which would remove not only the Bakrie family but two other large shareholders, chairman Samin Tan and board director Rosan Roeslani, who have close ties to the family.

Bumi said that the two shareholders, who hold their investments through coking coal miner PT Borneo Lumbung Energi & Metal (BORN.JK) and Bukit Mutiara respectively, have indicated to the board that they had "no intention of selling on the terms of the" proposal put forward by Mr. Rothschild's group of investors.

"The Independent Non-Executive Directors are continuing to work through a number of very complex issues as quickly as possible with a clear focus on maximizing shareholder value," Sir Julian Horn-Smith, the company's independent executive director said. Bumi, however, noted that it has been engaging with U.K. regulators over the findings of the investigation and wouldn't be in a position to recommend a course of action until regulatory processes were sufficiently advanced.

Nevertheless, the company said the board "is working towards a transaction which separates the Bakrie Group from the Company and divests the company's minority interest in Bumi Resources as soon as practical."

Bumi said that an independent probe launched by U.K. law firm Macfarlanes LLP on Sept. 24 confirmed the Bakrie Group's view that the information furnished for the investigation was obtained illegally by email hacking, but it noted that "these matters do not affect the seriousness with which the Board is treating the allegations."

The board didn't disclose much about the findings of the investigation, except to say that it didn't believe further write-downs would be necessary given that Bumi had already written down to zero its share of the $600 million in development assets at Bumi Resources that are the main focus of the investigation.

Bumi did, however, say that it would take an impairment charge at the end of the year related to the value of its 85% stake in PT Berau Coal Energy TBk (BERAU.JK) due to a drop in thermal coal prices.

It also said unequivocally that it had never planned nor would plan to recommend the sale of Berau on the terms proposed by the Bakrie Group.

The debt-laden Bakrie Group had proposed buying back the Berau stake sometime next year for about $950 million as the third transaction in its three-part exit plan, a move which Mr Rothschild and minority shareholders want to block despite chairman Samin Tan's willingness to accept the offer.

Mr. Rothschild and minority shareholders has proposed an alternative deal which would allow Bumi to sell its 29% Bumi Resources stake to the Bakrie Group in exchange for the Bakrie family's exit from Bumi's shares plus $278 million in cash. That sale would be interconditional on Mr. Tan and Mr. Roeslani agreeing to exit their investments.

The Bakrie Group wasn't immediately available for comment when contacted by Dow Jones.

Write to Alex MacDonald at alex.macdonald@dowjones.com

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