The petition, filed with the Supreme Court of British Columbia on Tuesday, asks the court to order Telus to provide information about how shareholders voted on a proposal to eliminate the company's dual-class share structure.
Telus has since withdrawn its proposal to convert its non-voting shares into a common class of voting shares after acknowledging that Mason Capital would have defeated the plan in a shareholder vote.
The telecom company says the legal filing is a "tactic" by the hedge fund to improve its own short-term profits at the expense of other shareholders.
Mason Capital has said it's concerned that Telus has exceeded the 33.3 per cent limit of foreign owners.
The hedge fund, which owns almost 20 per cent of Telus, says in the legal document that knowing the level of support for the proposal could affect Mason's decision about whether it should increase or decrease its stake in the telecom company.