Gartmore has confirmed it intends to float on the London Stock Exchange next month.
The fund management firm says it will use the proceeds of the flotation to reduce its net debt to approximately £150m.
Hellman & Friedman, the US private equity firm which owns Gartmore, has appointed BofA Merrill Lynch, Morgan Stanley and UBS as joint co-ordinators and bookrunners. Citi is also acting as a bookrunner.
Gartmore says the firm's directors and employees - who currently own 50% of the firm - will sell around one-fifth of their shares. Their remaining shares will be subject to a staggered lock-in arrangements, which expire in 2013.
Gartmore chief executive Jeffrey Meyer says: "We believe that a stock market listing now is the logical next step in Gartmore's development.
"It will raise the profile of the Group and provide benefits for our clients, shareholders and current and prospective employees. The fundamental prospects for our business are attractive and we have a clear strategy in place to deliver further growth."
Gartmore had £21.8bn of assets under management as at September 30.
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