Archipelago Holdings Inc. has entered into a definitive agreement to sell Wave Securities LLC, its wholly owned introducing broker subsidiary, to Merrill Lynch & Co. Inc.

The sale of Wave Securities by Archipelago was obligated by an order of the Securities and Exchange Commission as part of Archipelago’s acquisition of the Pacific Exchange Inc., in September 2005. The transaction, which is subject to NASD and NYSE regulatory approvals, is expected to close in the first quarter.

Jerry Putnam, Chairman and CEO of Archipelago, commented, “Wave Securities has played an important and unique role in the evolution of Archipelago from an ECN to a full-fledged exchange. With Merrill Lynch, Wave Securities will be well positioned to serve the growing needs of its institutional clients.”

Mike Stewart, head of Global Cash Equity Trading at Merrill Lynch, said, “Wave Securities has been a leader in providing electronic trading solutions to the institutional marketplace and will be a valuable complement to our industry leading equity franchise. We are pleased to welcome the Wave management, sales and support team to Merrill Lynch.”

“Wave is excited to be joining a team with vision, global reach and a complete suite of institutional products. We look forward to offering traditional and hedge fund managers a broader relationship with Merrill Lynch along with our electronic trading expertise and service,” said Joseph Lombard, president of Wave Securities.