NEW YORK (Bloomberg) — Invesco Limited, manager of the Aim mutual funds, began trading on the New York Stock Exchange after switching its primary listing from London because more than half its shareholders are based in the US.

Invesco, which managed $521 billion at the end of October, removed its shares from the London Stock Exchange at the end of trading on Monday. A secondary Toronto Stock Exchange listing and American depositary receipts in New York also were pulled.

The investment firm proposed the move in September, following a July announcement that it had lost foreign private-issuer status in the US because US residents owned a majority of its shares.

As a result, the company became subject to both US and UK accounting rules. The change makes the US Securities and Exchange Commission its main regulator.

"Moving our primary listing to the New York Stock Exchange eliminates the possible disruption associated with dual regulatory and accounting standards," president and chief executive officer Martin Flanagan said last week.

Invesco rose one cent to $27.24 at just before midday in New York Stock Exchange composite trading. The stock rose 11 percent this year, compared with a 14 percent gain for the Standard & Poor's Supercomposite Asset Management and Custody Banks Index.

Flanagan said in the statement the New York listing would boost the company's visibility in a "critical" market. US clients withdrew $5.2 billion from Invesco funds in the third quarter, while clients in Asia and the UK added $3.7 billion and $2.1 billion.

The company, previously called Invesco Plc, changed its domicile to Bermuda from the United Kingdom. Invesco, whose headquarters remain in Atlanta, said it plans to seek a secondary listing in London in early 2008.

The company merged with UK money manager Britannia Arrow in 1988, gaining its London listing. Invesco was named Amvescap until earlier this year.