Origin Energy Ltd. rejected a US12.8 billion Brookfield Asset Management Ltd.-led takeover, after the fund’s yearlong pursuit of a utility that’s vital to Australia’s energy transition.

About 69 per cent of ballots cast by investors were in support of the deal, below the required threshold of three-quarters of the votes, Origin said Monday in a statement, following a shareholder meeting. 

The utility will “focus on delivering on our strategic priorities, accelerating investment in cleaner energy and storage and pursuing our ambition to lead the energy transition,” Origin Chairman Scott Perkins said in the statement.

Origin’s largest investor AustralianSuper, which holds about 17 per cent of the company, had opposed the offer as too low, effectively blocking the prospects for an acquisition. The intervention by Australia’s largest pension fund showcased an increasingly assertive approach from managers of the country’s A$3.5 trillion retirement savings pool.  

“The value and future value of Origin is better in the hands of members and other shareholders rather than a private equity consortium seeking to make a quick return,” AustralianSuper said in a statement.

Origin’s shares fell 3.9 per cent to A$7.86 Monday, before trading was halted ahead of the vote.

Brookfield and EIG Global Energy Partners, which made a first offer in November last year, revised their proposal last month and the deal value was A$9.39 a share, based on Wednesday’s exchange rate, Origin said last week.

Origin’s board had supported the proposal, though last week rebuffed a suggested alternative transaction under which Brookfield would pay A$12.3 billion for the company’s energy generation and retailing business in the event of an unsuccessful takeover vote.

“Brookfield will evaluate its next steps, if any, with respect to Origin,” the Canada-based investment fund said in a statement. Executives have flagged Brookfield, which planned to acquire Origin using its Global Transition Fund, won’t return with any immediate new offer and intends to review the implications from new Australian energy policy.

Australia last month announced plans to expand its efforts to lure clean energy investment amid concerns deployments are not happening fast enough. Investment in renewables in the country fell close to a record low in the third quarter, according to BloombergNEF. 

The rejection of Brookfield’s plan threatens to slow Australia’s attempts to accelerate the addition of solar and wind farms as aging coal-fired plants are shuttered. Brookfield had pledged to invest as much as A$30 billion over 10 years in Origin and to more than triple the utility’s planned clean energy generation capacity. 

AustralianSuper is open to providing capital to assist Origin’s transition, the fund said in its statement, reiterating an earlier pledge.

“There’s going to be no shortage of opportunities for co-investment alongside Origin through the transition, so we would welcome that from all parties — the cheaper the cost of capital the better,” Perkins said.

With assistance from Amy Bainbridge.