Mittleman Brothers has taken a stake in Aimia Inc. and says it may push for changes to the Canadian loyalty-card provider’s management or board as well as seek a sale of all or part of the company.

The investment firm first disclosed in September a stake in Aimia, which runs Air Canada’s loyalty program Aeroplan. Last week, Mittleman said it had increased its ownership of Aimia to 10.6 per cent at the end of January, and opened the possibility of pushing for changes at the company, according to an updated regulatory filing.  

In addition to governance changes, the firm said it may also push for changes to Aimia’s capitalization or dividend policy, the filing shows.

Representatives for Melville, New York-based Mittleman and Aimia in Montreal declined to comment.

Aimia’s shares have fallen more than 70 per cent since May when Air Canada said it planned to launch its own loyalty program outside of its partnership with Aimia. Earlier this month, Aimia said it agreed to sell its loyalty program Nectar to J. Sainsbury Plcfor 60 million pounds ($83 million).

Mittleman Brothers, run by Christopher, Phillip and David Mittleman, has held activist positions in the past at Carmike Cinemas Inc. and Revlon Inc. It is primarily focused on long-term investments in what it deems to be severely undervalued securities, according to its website.