When the Unlawful Internet Gambling Enforcement Act hit in 2006 many online poker sites, including industry-leading PartyPoker, decided to vacate the U.S. market as a precautionary measure.

And when those online gaming giants pulled out, it left the door open for sites like PokerStars, Full Tilt and Absolute/UB Poker to dominate.

And dominate they did.

In the years following UIGEA, PokerStars, Full Tilt and the CEREUS Poker network sucked up over 60% of the online poker market share and brought in hundreds of millions in profit.

Here is a closer look at the so-called big three in their prime from 2006-2011 easy cards tricks:

PokerStars Gets Busy with International Poker Tours, WCOOP, Daniel Negreanu

With PartyPoker gone, PokerStars was heir to the throne in the U.S. and the site certainly didn’t waste its opportunity.

PokerStars boasted software that was among the best in the industry, a group of pros that included WSOP Main Event winners Chris Moneymaker, Greg Raymer and Joe Hachem, and it was ready to make its case as the best poker site in the world.

The sheer numbers behind PokerStars at its peak from 2009-2011 were astonishing. Consider for a minute:

• It was not unusual to see more than 200,000 players logged in at the same time.
• The site broke the Guinness world record for most poker players in a tournament at 200,000 players.
• PokerStars also broke an unofficial cash game record when it had 105,000 players playing at the same time in late 2010.
• As of March, 2012, there have been over 75 billion hands recorded on PokerStars.

Not content with dominating the online market, PokerStars also launched a series of live tournaments starting with the uber-popular European Poker Tour in 2004 but eventually expanding to include the Asia Pacific Poker Tour, the Latin American Poker Tour and even the short-lived North American Poker Tour.

The PokerStars Caribbean Adventure became one of the most popular tournaments in the world with thousands of players descending on Nassau to play live poker every year.

The site dominated the online tournament world and was the only major site to have a weekly tournament that offered a $1 million guarantee.

PokerStars also pioneered online poker series such as the World Championship of Online Poker and later the Spring Championship of Online Poker.

Perhaps the biggest pro signing in the history of PokerStars, outside of Chris Moneymaker, came when they inked Daniel "Kid Poker" Negreanu to a deal in 2007.

The Canadian pro was one of poker’s biggest free agents and even had his own poker skin, Full Contact Poker, but decided to join forces with the industry giant.

It was a move that paid off for both parties as Negreanu continued to be the darling of the poker world while PokerStars secured one of the bona fide top three most recognizable players as the face of the site.

They further augmented the team by signing upcoming stars like Jason Mercier, Liv Boeree and Viktor "Isildur1” Blom as well as a number of regional poker celebrities.

Full Tilt Takes Cash-Game Crown, Solidifies Pro Team, Introduces Onyx Cup

PokerStars wasn’t the only player in the post-UIGEA poker world. Not by a long shot marked cards.

Full Tilt Poker busted on to the scene in 2004 and quickly built a following by having arguably the best pro team in poker with Phil Ivey, Erik Seidel, Chris "Jesus” Ferguson, Howard Lederer and Erick Lindgren.

The FTP slogan was "Learn, Chat and Play with the Pros" and the poker world responded by flocking to the site in droves.

FTP became the home for high-stakes professionals with millions of dollars being swapped back and forth between players like Viktor "Isildur1” Blom, Phil Ivey, Tom Dwan and Patrik Antonius.

Full Tilt Poker didn’t let up in its relentless pursuit of big names either as dozens of players were signed as "Red Pros” which usually meant they got some combination of rakeback and an hourly wage for playing on the site.

In later years FTP would also sign high-stakes gods Patrik Antonius, Gus Hansen and Tom "durrrr" Dwan and further solidify its place as the home of the biggest games on the internet.

Although Full Tilt never got into the live tournament scene the way PokerStars did, they were a major player at the Aussie Millions and sent a large portion of their team to the popular event every year.

In 2007 FTP also made headlines by finally nabbing a WSOP Main Event winner in Jerry Yang.

Just prior to Black Friday in 2011, Full Tilt Poker also announced a special Onyx Cup tournament series that would have been a six-tournament tour with buy-ins ranging from $100,000 to $300,000 for some of the best, or at least richest, poker players in the world.

PokerStars usually gets more credit for pioneering the online poker game but it’s worth noting that Rush Poker was developed by Full Tilt Poker and it was one of the first sites to offer rakeback.

Full Tilt Poker also hosted the massively popular Full Tilt Online Poker Series (FTOPS) every few months.

There were many players who held fast to the notion that Full Tilt’s software was simply better than PokerStars.

UB Poker, Absolute Poker Merge to form CEREUS

Thanks to several cheating scandals, the history of UB Poker and Absolute Poker isn’t nearly as glamorous as PokerStars or Full Tilt but the fact remains they were a major player in the online poker industry for much of the 2000s.

UB Poker had two of the biggest poker pros in the world in Phil Hellmuth and Annie Duke. The powerhouse pair were used on TV shows like The Best Damn Poker Show on Fox Sports Net and Duke went on to star in Celebrity Apprentice on CBC.

Both UB Poker and Absolute Poker were very active at the WSOP and had VIP lounges for their pro team. UB Poker also sponsored the Aruba Poker Classic.

In the late 2000s UB Poker went on a major pro-signing spree and hired Joe Sebok as its media and operations consultant.

UB was also a major advertiser on Sebok’s Poker Road pokertainment site and the short-lived Poker2Nite TV show with the aforementioned Sebok and Scott Huff.

Absolute Poker and UB Poker were owned by the same company so in 2008 they made the decision to merge and form the CEREUS Poker Network, which shared players from both sites.

Despite the site’s success there were always vocal detractors. Daniel Negreanu blasted Prahlad Friedman for signing with the site in early 2011. He posted this Tweet as a response to the signing.

"Imagine a world where crooks weren’t held accountable and continue to rob people with no recourse? The world should know… I’m all about 2nd chances in the right circumstances; this isn’t one. They are no more transparent today than in the past.”

That statement proved prophetic as the CEREUS Poker network closed its doors after Black Friday and has yet to pay back its players.

The U.S. Department of Justice Takes Aim

You may wonder why the U.S. government was sitting idly by while offshore poker sites continued to rack in hundreds of millions of dollars in profit after UIGEA passed.

It turns out they weren’t.

The U.S. Department of Justice were in the process of building a massive case against the three sites based on the way they processed payments.

Playing online poker is not illegal. It never has been. Technically the UIGEA only restricts banks from processing payments from players.

PokerStars, Full Tilt Poker and CEREUS got around this by using third-party payment processors who figured out a way to get cash from U.S. players to the offshore poker sites.

One such processor was Australian Daniel Tzvetkoff, the former head of Intabill. Tzvetkoff was arrested in Las Vegas in 2010 by the FBI and charged with money laundering, bank fraud and wire fraud.

Tzvetkoff faced a severe prison sentence but was released a few months later and reportedly turned state’s evidence to form the basis for U.S. Attorney Preet Bharara’s case against the big three online poker sites.

The result was the United States vs. Scheinberg, a criminal case against PokerStars, Full Tilt Poker and CEREUS that alleges the founders took part in bank fraud and money laundering to process their players’ funds.

Since Black Friday none of the big three have offered for real-money poker games in the United States.

For a full accounting of what's happened since Black Friday, check out our Black Friday Bulletin Board.