On August 7, 2025, Ontario Teachers’ Pension Plan Board has agreed to sell its stake in Diot-Siaci, a European corporate insurance brokerage, to Ardian. Ontario Teachers’ acquired its position in 2021 to support the merger of Diot and Siaci Saint Honoré. Since then, revenues have grown from about €700 million to more than €1 billion (C$1.03 billion to C$1.47 billion at the time). The group has also expanded its reach into the Middle East and Africa and pursued acquisitions, including the Nasco reinsurance business.

Ontario Teachers’ contributed to the merger integration, international expansion, and growth in niche areas such as HR consulting. The investment is part of its C$13 billion Financial Services & Insurance portfolio, which has completed 15 global transactions, with most led or co-led by Ontario Teachers’.

The parties did not disclose the transaction value. The deal remains subject to regulatory approvals and customary closing conditions, with completion expected later this year.