Onex Corporation has agreed to acquire USI, one of the top ten U.S. providers of insurance brokerage services.

Onex plans to purchase the company for $2.3 billion, with the transaction slated to close by the end of 2012.

USI offers a diversified mix of property and casualty insurance, employee benefits and retirement consulting. It’s headquartered in Briarcliff Manor, New York and has more than 3,300 employees across the U.S.

The equity investment of approximately $700 million will be made by Onex Partners III, in which Onex is a 25% limited partner. Onex will be a co-investor in the transaction.

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