Two of Canada's top pension fund managers, Ontario Teachers' Pension Plan Board and the Canada Pension Plan Investment Board (CPPIB), last week both outlined plans to oppose the bank's pay structure in a nonbinding vote.

The investor pushback was in response to payouts being made to former Chief Executive Gerry McCaughey, who retired in September 2014, and Richard Nesbitt, its former chief operating officer, who retired a month later.

Earlier this month, CIBC announced that the two executives together stand to receive roughly C$25 million ($20.5 million) in post-retirement pay due to an acceleration of their retirement timetables.

CIBC said that more than 56 percent of the votes cast on the matter at its annual meeting in Calgary on Thursday opposed its executive pay structure.

Proxy advisory firm Institutional Shareholder Services (ISS) had also publicly slammed the payout earlier this month.

The investor outrage comes amid a growing outcry about large pay packages for senior executives at some Canadian companies.

Barrick Gold faces fresh backlash over executive pay at its shareholders meeting later this month, with some big institutions planning to vote against its compensation plan and withhold votes for directors to protest a $12.9 million pay package for its Executive Chair John Thornton.

(Writing by Euan Rocha; Editing by Meredith Mazzilli)

By John Tilak