The acquisition will be completed in first quarter of next year and will add to 2009 earnings, the companies said in a statement on Wednesday.

The deal was approved by both boards and requires further regulatory approvals.  Chief Executive Officer Robert Greifeld has negotiated four other acquisitions this year. Gaining control of Philadelphia market would make Nasdaq third-biggest exchange in the $1 trillion US options industry, where trading is growing at quickest pace in seven years.

Clearing business

This year Nasdaq acquired closely held Directors Desk to offer more online services to corporate boards.

It also bought Boston Stock Exchange for $61 million to expand equity trading and enter the transaction clearing business.

Nasdaq shareholders may vote as soon as next month on $4.8 billion purchase of Stockholm-based OMX AB through a joint bid with Borse Dubai, according to a regulatory filing earlier this week. Nasdaq has also agreed to acquire one-third stake in Dubai International Financial Exchange for $50 million, the filing shows.

Failed LSE bid

Greifeld, 50, had tried to expand overseas since March 2006, failing twice to buy London Stock Exchange Plc. Nasdaq’s sale of its 31 per cent stake in London bourse helped boost third- quarter profit 12-fold to a record $365 million.

The Philadelphia exchange, led by CEO Sandy Frucher, has failed to reach deals after holding takeover talks with brokerages and exchanges in the past.