There's one thing you can bet on if Nasdaq OMX Group succeeds in buying the New York Stock Exchange: NYSE Euronext CEO Duncan Niederauer won't be sticking around.
It's no secret that Niederauer and Nasdaq Chief Executive Robert Greifeld don't see eye to eye, and their professional rivalries have frequently erupted into open hostilities.
Leading figures in the exchanges industry say Greifeld, 53, won't tolerate having Niederauer, 51, around -- or vice versa -- should Nasdaq and Intercontinental Exchange succeed in their $11.3 billion takeover bid for NYSE Euronext.
"One can never discount egos in our world. It's been a long tough fight for Mr. Greifeld, being the underdog," said Thomas Caldwell, head of Toronto-based Caldwell Securities Ltd, one of the biggest investors in the exchanges industry.
"You're the guy who's been always fighting uphill - you can get into that role of competing, of finally being able to take out your tormentor," he said.
Nasdaq and ICE on Friday announced an unsolicited bid for NYSE Euronext, in a move to undo Deutsche Boerse's deal with NYSE Euronext in February.
The move comes after Nasdaq and NYSE have spent decades sniping at each other, from how they handle stock trades to bragging rights over which exchange draws the best IPOs.
Nasdaq has won the listings of companies such as DreamWorks and News Corp from the NYSE in recent years. But, despite Greifeld's efforts to change Nasdaq's image as a tech-focused venue, it has lost out to the NYSE on mega-IPOs such as General Motors.
On occasion, the animosity between the exchanges has come straight from the top. At a conference in New York in June 2008, Greifeld spoke mockingly of NYSE's falling U.S. equities market share, prompting an angry riposte by Niederauer.
Last year, Greifeld was on CNBC blaming NYSE for the May 6, 2010 flash crash during which the Dow Jones index fell 1,000 points within minutes.
The bespectacled Greifeld's scrappy, pugnacious management style comes from his days as a tech entrepreneur who built systems used in Nasdaq's trade order management system.
In contrast, Niederauer spent 22 years at Goldman Sachs, making him firmly part of Wall Street's establishment.
The two men are almost never seen at the same event together, even at industry functions.
"There'd be no need for two strong U.S. leaders," Larry Tabb, CEO of trading consulting firm Tabb Group, said of a combined NYSE-Nasdaq.
On a call with analysts and media on Friday morning, Greifeld said he had not yet discussed the bid with NYSE management, adding he envisioned a "meritocracy" in deciding positions.
IN NEED OF OWN MEGA-DEAL
Greifeld took the reins of Nasdaq in 2003, when it was bleeding U.S. market share to electronic communications networks (ECN), which offer off-exchange trading, and being squeezed by a decline in IPOs after the tech bubble burst.
The New York native immediately sought to get rid of Nasdaq's money-losing ventures, such as a platform to list companies not eligible for inclusion on its small-cap market.
Once Nasdaq regained its footing, in 2005, Greifeld set out to make acquisitions. His first large buy was a $1.9 billion deal for Instinet, an ECN.
Greifeld's first attempt at an exchange takeover was a miserable failure, however. His $5.3 billion bid in 2006 for the London Stock Exchange won support from just 0.4 percent of LSE shareholders.
Pressure on him to nab an overseas exchange grew intense when NYSE bought Euronext, a group of European stock exchanges, for $14 billion later that year.
In 2008, Greifeld finally landed a major international deal: Scandinavia's OMX. He then bought the Philadelphia and Boston stock exchanges, turning Nasdaq into an options powerhouse, competing with CBOE and NYSE's Amex.
Those deals transformed Nasdaq from a U.S. stock trading venue into a company with operations in 22 countries.
"Our mission is to focus first on being the predominant U.S. equities market," Greifeld said in 2003.
As for Niederauer, he has not yet had the chance to oversee a mega-merger since the NYSE Euronext deal was orchestrated by his predecessor, John Thain.
Niederauer has so far only done smaller deals, but the politically savvy executive has endorsed the Deutsche Boerse bid, which would let him emerge from Thain's shadow and become head of the largest exchanges operator in the world.
"As the rest of the world develops and is looking for a valuable, global and diversified partner, we will hopefully be their first choice," Niederauer said in February. A merged Deutsche Boerse-NYSE Euronext will be "the inviter, the enabler, the convener with other exchanges," he said.