Electronic trading system

Instinet

(INET)

opened well above its initial public offering price Friday, the company's first day of trading on the

Nasdaq.

Instinet, a unit of news and financial data company

Reuters

(RTRSY)

, opened at $17. The company sold 32 million shares, 2.5 million more than expected, at $14.50 each on Thursday.

Reuters will retain more than 86% of Instinet after offering about 14% of the company to the public. Instinet raised $464 million in the IPO.

Shares of Instinet recently gained $3.67, or 25.3%, to $18.17. About 21.4 million shares had changed hands by midday.