The Globe and Mail reports in its Thursday edition that Conservative MP Adam Chambers is calling on the federal Competition Bureau to review the impact of Canada's Big Five banks' growing dominance of the mutual fund sector. The Globe's Clare O'Hara quotes Mr. Chambers saying their decision to stop selling third party investment funds has dramatically increased their influence while harming branch customers. In a letter sent ahead of Thursday's federal budget, Mr. Chambers asks the bureau to review the banks' decision and if warranted, initiate an investigation, publish a market study, or pursue legal action. The Big Five started removing competitors' mutual funds around 2021. Although various groups have raised concern over the years, no formal action has been taken against the move. The banks' total market share of mutual fund assets has grown to 50 per cent in 2026 from just 20 per cent in 2000, Mr. Chambers, who previously worked in financial services, said in his letter. "All options, no matter how aggressive, should be considered including commencing legal action against the incumbents for anti-competitive conduct and abuse of dominance in their branch networks," he wrote. One option is to amend the Bank Act.