Instinet Group’s Shares Plummet 14%

Instinet Group Inc.’s shares fell 14% Tuesday to their lowest price since the electronic brokerage and trading firm went public in May, as investors fretted that the company’s market share may erode further.

“There is a lot of concern the trading business is migrating to other venues,” said Paul Stocking, an analyst at American Express Financial Advisors.

Instinet (INET) fell $1.15 to $7.05, about half the $14.50 the company fetched in its initial public offering.

London-based Reuters Group (RTRSY) owns 83% of Instinet.