Greenberg Traurig LLP, one of Washington’s fastest-growing lobbying shops, has received one of K Street’s biggest payout.

The firm received a $4.2 million, one-time payment earlier this year for helping hundreds of American terrorism victims collect $116 million in damages from Saddam Hussein, according to newly released lobbying disclosure statements.

The payment, which is the largest lobbying fee recorded since a 1995 law required K Street firms to disclose their earnings, eclipses the $4 million bonus the same shop reported two years ago for securing a similar claim against the Cuban government.

The massive payments show that Greenberg Traurig and Republican lobbyist Jack Abramoff are profiting from a lucrative niche in the lobbying world that opened just a few years ago when Congress first allowed U.S. victims of terrorism to collect judgments from foreign governments.

“This could be an interesting field of work for lobbyists,” said Gary Shiffman, a Greenberg Traurig lobbyist who specializes in terrorism cases. “There are a lot of other cases floating around. We get a lot of calls.”

Indeed, the total of $8.2 million that Greenberg Traurig has received so far may be only the tip of the iceberg.

The firm is representing hundreds of other Americans who were killed, injured or tortured by terrorist groups in Iraq, Iran or Libya over the past two decades.

If U.S. courts find the rogue governments responsible, Greenberg Traurig could ring up millions more by helping those clients collect judgments.

The $4.2 million received so far this year came after the firm helped three separate sets of clients get their hands on Iraqi funds to settle their court judgments.

Late last year, lobbyists for the firm helped tuck a provision into a terrorism reinsurance bill that ensured that their clients could tap into nearly $2 billion in frozen Iraqi assets.

As a result, more than 200 Americans who were used as human shields in the 1991 Persian Gulf War finally collected $93 million in damages; four Americans who were kidnapped by Hussein in the mid-1990s received $20 million; and an American who survived an Iraqi assassination attempt picked up $75,000.

Despite the record-setting $4.2 million bonus, the Greenberg Traurig stands to make millions more from other work in the arena.

The firm represents another 300 American human shields who are in the middle of a second legal proceeding.

If the case tracks its predecessor, Iraq could owe the Americans $139 million, which could hand Greenberg Traurig a $4.65 million bonus — another new record.

Outside of Iraq, the firm represents two Americans who are suing Libya after they were abducted, tortured and held hostage by the Libyan intelligence service in the 1980s.

The firm also signed up three Americans who were killed or injured in terrorist acts committed by Iranian-backed terrorist organizations, including the American shot and kicked out of a hijacked plane in Tehran in 1984.

Two of the three clients in the Iranian cases have won judgments of $42 million and $33 million against Iran, respectively, but have yet to collect. The firm also is nearing a deal with another set of terrorism victims.

U.S. and international law had precluded Americans from suing foreign governments until recently. But in 1996, Congress approved legislation that allowed U.S. citizens to collect damages from countries thought to sponsor terrorism, including Iran, Iraq, Libya, Syria, Sudan, North Korea and Cuba.

Since then, a growing number of Americans have hired Washington lobbyists to help them collect judgments handed down by U.S. courts.

In one of the first cases, Greenberg Traurig helped win a $96.7 million settlement from the Cuban government after its air force shot down three Cuban-Americans as they tried to rescue refugees floating toward the U.S. mainland.

After a U.S. District Court judge issued the judgment, Greenberg Traurig lobbyists helped the families cash in by moving legislation that let the families seize frozen Cuban assets in the United States.

Greenberg Traurig earned a $1.3 million fee from each of the families, for a total of $4 million.

With acts of international terrorism seemingly on the rise, Greenberg Traurig and the handful of other Washington firms that handle such cases could see their workload increase in the coming years.

“Unfortunately, this has developed as an area because these attacks have continued,” said Karen Williams of Crowell & Moring, a firm that represents the Beirut Bombing Victims.

But the work is getting more difficult as well. Soon after Greenberg Traurig secured a win in the Iraq cases, the U.S. government transferred Iraq’s remaining frozen assets to Baghdad to help rebuild the country.

Meanwhile, the State Department is pushing legislation that would make it harder to collect from foreign governments.

Still, for a thriving lobbying firm on K Street, the multimillion-dollar payments are good for business.

In part because of the $4.2 million payment, Greenberg Traurig now ranks as the No. 3 ranked lobbying shop on K Street, according to Roll Call’s survey of lobbying receipts for the first six months of this year.