OMERS, the pension plan for Ontario's municipal employees, will acquire a 40% interest in Fairfax Financial Holdings Ltd.'s runoff group, RiverStone Insurance (UK) Ltd.

The cash purchase price of at least $560 million will result in Fairfax Financial recording a gain of approximately $280 million before tax, subject to certain book value adjustments at closing.

Upon the deal's completion, Fairfax will deconsolidate the U.K. runoff group and apply the equity method of accounting for its remaining interest. At some point in the future, Fairfax may further monetize its remaining interest in the group, although the company also retains the flexibility to repurchase its interest over time.

Luke Tanzer will remain CEO of RiverStone Insurance.

The transaction remains subject to regulatory approval and is expected to close in the first quarter of 2020.