TA Associates, a global growth private equity firm, will take over the OMGI business from January 2018 the company confirmed on Tuesday morning.
The deal is valued at £600m ($802m, €681m).
The announcement ends months of rumours as to what deal would be struck with a number of names, including OMGI chief executive Richard Buxton himself, thrown into the ring as potential buyers.
Buxton and the majority of the senior leadership team will remain in place and all assets, which grossed £198m in December 2016, transferred.
The sale of the single strategy OMGI business plays into Old Mutual Wealth’s major restructuring of the business which includes the “managed separation” of its four core businesses into separate companies.
OMGI has now split from the Old Mutual Wealth multi-asset arm, which will be headed by Paul Simpson and rebranded as Quilter Investors in 2018.
Paul Feeney, chief executive of Old Mutual Wealth, said: “Ahead of our managed separation and proposed listing in 2018, we are pleased that we have completed the strategic review of the Single Strategy business and agreed terms for a transaction with TA Associates.”
Buxton added: “The management team is delighted to be partnering with TA Associates to buy the single strategy business. I believe this is a good outcome for our customers and our staff.”
Funds under management at OMGI hit £25.7bn as of 30 September this year, with operating profits in the first half of the year hitting £36m, £17m of which came from performance fees.