SolGold faces a possible shareholder revolt as the mining heavyweights that backed the company and its huge Ecuadorian copper deposit grow increasingly frustrated by the management’s decisions.

BHP Group is SolGold’s biggest shareholder and Australian gold major Newcrest Mining is No. 2, having both positioned themselves for a seat at the table when it’s time to finance and build the project. Neither was pleased with SolGold’s decision earlier this year to sell a royalty stream -- while the deal provided funding, it meant giving up a piece of future profits. The company has also faced setbacks in its mine-planning process.

SolGold’s annual shareholder meeting Thursday offers a chance for investors to have their say. The company has recently made changes to its board, including adding independent directors.

Amid concerns about corporate governance, major investors BHP and Cornerstone Capital Resources were considering whether to vote against re-electing certain board members, including SolGold CEO and co-founder Nick Mather, according to people familiar with the matter. The people asked not to be identified discussing private deliberations before votes were submitted ahead of the meeting.

It’s not clear what Newcrest was planning, but it has been a vocal critic of SolGold’s decisions, particularly the $150-million royalty deal. Cornerstone has clashed repeatedly with SolGold and fought off a hostile takeover approach from the company earlier this year. Together, BHP, Newcrest and Cornerstone own about 35% of SolGold.

“We have to look after the interests of all shareholders,” said Ingo Hofmaier, SolGold’s acting chief financial officer. “The royalty was at a valuation that exceeded the market value at the time and was the superior offer at the time.”

While it’s still years -- and billions of dollars -- away from producing any metal, SolGold has drawn attention from across the mining industry because of the size of its Cascabel copper project. The deposit is one of the largest undeveloped mines in the world for a crucial metal that’s forecast to be in tight supply for years to come. The company also has licenses to explore large swathes of Ecuador for copper.

The investments by BHP and Newcrest prompted speculation that SolGold could be a takeover target, especially after BHP increased its stake last year to become the biggest shareholder. Both companies had said they’d rather SolGold sell shares to raise money, with BHP making the comments before the royalty deal was announced, and Newcrest afterward.

After criticising the financing plan, Newcrest withdrew its representative, Craig Jones, from the SolGold board, and declined to participate in a smaller equity raising at that time.

BHP and Newcrest both declined to comment.

Investors have also been concerned by SolGold’s progress on the project. Earlier this month, the company said it will have to redesign parts of its planned underground mine and that a study on its development would be delayed, which analysts said would likely increase the cost.

SolGold, meanwhile, has made sweeping changes to its corporate governance this year, while facing public criticism from Cornerstone. Brian Moller stepped down as chairman and the company appointed a raft of new independent directors, including Kevin O’Kane, a former BHP veteran. It also reconstituted its board committees.