More than 99% of Coal and Allied shareholders voted in favour of the acquisition at a scheme meeting held in Sydney.
Subject to court approval, Coal & Allied will issue shareholders $117 per share from Rio Tinto via Hunter Valley Resources and a special dividend of $8 per share.
Coal & Allied said it would apply to the Federal Court of Australia for approval of the scheme at a hearing on Wednesday.
If approved, the scheme will take effect on Thursday December 1, which will also mark the last day of trading for Coal & Allied.
Rio and Mitsubishi announced their original proposal on August 8, offering Coal & Allied shareholders $122 a share for the remaining stake in the company.
An increased bid of $125 was then made on August 29 after a proposal response committee made up of Coal & Allied directors Bryan Davis, Chris Renwick and Annabelle Chaplain reviewed the initial indicative proposal.
Rio Tinto Energy chief executive officer Doug Ritchie said the acquisition was an excellent outcome for the company.
“Rio Tinto and Mitsubishi Development have been long-term shareholders in Coal & Allied and it will be business as usual for our employees, contractors and suppliers,” Ritchie said.
“Rio Tinto Coal Australia will continue to manage Coal & Allied, pursuing the existing operational strategy and planned development projects.”
Rio Tinto currently owns 75.7 per cent of Coal and Allied, and Mitsubishi 10.2 per cent.
Rio Tinto first started accumulating an interest in Coal & Allied in 1977 and by 1991 owned 70% of the Hunter Valley miner.