Until Archipelago Holdings (NYSE:AX) announced its proposed merger with the New York Stock Exchange, not many people knew about the company. The electronic stock exchange specialist was putting out some great numbers and hooking up equity buyers and sellers through its ArcaEx platform, but it was mostly an obscure entity.

Thankfully, that didn't get in the way of subscribers to our Motley Fool Rule Breakers newsletter service. David Gardner recommended the stock in the February issue when it was trading at just $20.42 a share. The discovery process was catapulted into motion after the NYSE Group deal was announced. The stock has gone on to more than double, closing yesterday at a healthy perch of $44.50.

Archipelago provided another glimpse as to why NYSE Group wanted its hands on it when it released its June trading numbers yesterday. ArcaEx was responsible for 3.3% of all of the NYSE-listed stock trading that took place last month. That was more than double its 1.5% market share a year earlier.

Archipelago's presence was even greater on rival exchanges. ArcaEx accounted for 29.1% and 22.7% of the market trading volume on the American Stock Exchange and Nasdaq, respectively. More than a fifth of all trades for Intel (NASDAQ:INTC) went through Archipelago's network last month. Were you a buyer or seller of Sirius Satellite Radio (NASDAQ:SIRI) in the last 30 days? Well, ArcaEx had a hand in 15% of those transactions too. Need more proof? Nearly 180 million shares of Sun Microsystems (NASDAQ:SUNW) and 258 million shares of Microsoft (NASDAQ:MSFT) were swapped thanks to Archipelago in June.

It's not necessarily ironic that an exchange should be coveted by market traders. Archipelago isn't even alone; The Chicago Mercantile Exchange (NYSE:CME) and Nasdaq (NASDAQ:NDAQ) have also smoked out suitors lately.

Ahhh, the sweet smell of consolidation.

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Longtime Fool contributor Rick Munarriz thinks that bids and asks are romantic in the appropriate context. He does not own shares in any of the companies in this story. The Fool has a disclosure policy. He is also part of the Rule Breakers newsletter research team, seeking out tomorrow's ultimate growth stocks a day early.