Mike Cannon-Brookes, chief executive officer of Atlassian, attends the annual Allen and Co. Sun Valley media conference in Sun Valley, Idaho, U.S., July 11, 2019.
Mike Cannon-Brookes, chief executive officer of Atlassian, attends the annual Allen and Co. Sun Valley media conference in Sun Valley, Idaho, U.S., July 11, 2019. Reuters / BRENDAN MCDERMID

Tech billionaire Mike Cannon-Brookes is seeking to buy an 11.5% stake in AGL Energy nearly two months after Australia's top power producer rejected a A$5.4 billion ($3.8 billion)takeover offer from his Grok Ventures and Canada's Brookfield Asset Management, according to a market statement from JPMorgan.

"Grok Ventures and its affiliates are looking to acquire a combined physical and economic interest in up to 11.5% of AGL Energy Limited shares as part of a strategic derivative transaction," JPMorgan's equity capital and derivatives markets division said in the information statement seen by Reuters.

The statement said if the transaction goes ahead, Grok would announce its interest in AGL before the opening of trade on Tuesday.

The bid for a stake by Cannon-Brookes, co-founder of software company Atlassian Corp, was first reported by the Australian Financial Review.

The intended share purchase appears to be aimed at building a blocking stake ahead of a vote by AGL shareholders on a plan to split the company, rather than as a precursor to trying to acquire the company, the Australian Financial Review said.

AGL will ask shareholders to vote in June on a plan to demerge into an energy retailer, called AGL Australia, and a coal-fired power generation company, called Accel Energy.

A spokesperson for Grok declined to comment on Cannon-Brookes' intentions.

($1 = 1.4174 Australian dollars)