Australia’s top shareholder said on Thursday it would reject a complex new offer by a Brookfield Asset Management Ltd (BAM.AX)-led consortium to buy Australia’s most prominent energy retailer made after it became clear investors would vote down an earlier $10.6 billion bid. By lodging the amended offer just hours before a meeting of Origin shareholders in Sydney to vote on the original bid was due to start, suitors gave themselves more time to lobby investors.

The Australian superannuation fund said the revised deal was still substantially below its estimate of Origin’s long-term value. “This latest low-ball offer strengthens our view that the proposed acquisition is not in the best interests of its members,” it said in a statement.

Trading in Origin’s shares was halted on Thursday after the suits lodged a revised bid that involves splitting the business into two parts to try and secure the 75% vote needed for the takeover scheme of arrangement to go ahead. Under the terms of the new offer, Origin’s integrated gas business would be owned by Brookfield and US investment firm EIG Global Energy Partners. In contrast, its energy markets business would be sold off.

If the revised plan gets the go-ahead, Origin shareholders will receive an implied total payment of $9.43 a share for their current investments in the utility, which would be paid in cash and new shares. But the board said it had “significant reservations as to the complexity, conditionality and differing value of the new proposals” and would consider them before offering a view.

Investors have already expressed concern that the original Brookfield-EIG proposal was too expensive for Origin, which has a reputation for providing reliable and competitive electricity to Australian households and businesses. Some analysts have valued the company at over $10 a share, while others believe its value is closer to $8.50.

The battle for Origin reflects the challenges of valuing assets in the sector, where future supply and demand are uncertain, and the government is planning significant spending to lure new investment. The tussle over the country’s largest power generator also highlights the difficulty of dealing in a sector heavily influenced by policy intervention and regulation. Reuters business journalist Scott Murdoch contributed to this report.