Fisher Investments (FI) has secured an investment commitment in the range of $2.5bn-$3bn from Advent International and a 100% subsidiary of the Abu Dhabi Investment Authority (ADIA).

The minority investment values the US-based investment adviser at $12.75bn.

Ken Fisher, the founder of Fisher Investments, will maintain majority controlling stake in the company with voting shares of more than 70%. This will be after closing of the investment deal, which is anticipated to close later this year.

It forms a part of Ken Fisher’s estate planning for the long term. It is aimed at ensuring that Fisher Investments under the leadership of CEO Damian Ornani will maintain its independence as a privately held investment adviser and asset management firm.

Ken Fisher said: “This transaction is aimed dually at estate tax and planning purposes while assuring that FI will maintain its traditional culture, growth evolution and devotion to exceptional client service.”

Established in 1979, Fisher Investments oversees assets exceeding $275bn for a global clientele exceeding 150,000 clients. This includes 120,000 private clients in the US and 185 institutional clients worldwide.

The company is claimed to serve over 30,000 private clients across 16 countries. It maintains offices on four continents, with ongoing strategies to further extend its global reach.

As part of the deal, Ken Fisher, who is the firm’s executive chairman, will sell personal holdings to Advent International-managed funds and ADIA.

For Advent International and ADIA, the deal is said to be an opportunity for a long-term investment in one of the world’s largest investment advisers.

Investors in the Advent International vehicles include Lunate Capital managed funds, Mousse Partners, and Fisher Investments’ longtime largest institutional client, South Korea’s National Pension Service (NPS).

This is the first outside investment in Fisher Investments, with previous ownership in the firm held solely among family and employees.

Ornani said: “This transaction gives us the independent runway with truly exceptional institutional investors who can bring us their wisdom, value our unique culture and goals, and want us to keep doing what we’ve always done, bigger and better, while pioneering never yet done solutions to benefit our clients and employees.”

For the transaction, J.P. Morgan Securities and RBC Capital Markets acted as co-financial advisers, while Paul Hastings provided legal advisory services to Fisher Investments. Advent International, on the other hand, was represented by Ropes & Gray as legal adviser, while ADIA was advised by Gibson Dunn.