(Bloomberg) -- Javier Lopez has spent hundreds of hours interviewing Cuban exiles and meticulously building cases for families who lost property after the 1959 revolution. He’s pored over obscure legal papers, Spanish-language newspaper articles and, in one case, a century-old parchment deed. Then, he stashed the suits in his computer: No court would hear them, and he couldn’t bill a cent.

On Thursday, the cases can come out again.

For the first time, the Trump administration will allow lawsuits in U.S. courts against firms operating on seized Cuban property, including multinational corporations based in Canada and Europe, which accounts for the island’s biggest source of foreign investment. In many cases, the companies entered the market decades after the land was expropriated, but they could be held accountable all the same.

Some Cuba watchers are projecting a flurry of legal activity, while foreign governments and corporations are preparing to defend billions in assets. The European Union and Canadian governments have jointly warned that suits could prompt them to complain to the World Trade Organisation. Among potential lawsuit targets are Swiss food company Nestle SA; Canadian miner Sherritt International Corp.; and Spanish hoteliers NH Hotel Group SA and Melia Hotels International SA, according to a list from the U.S.-Cuba Trade and Economic Council.

Read a QuickTake: Why Trump Is Adding a Chill to U.S.-Cuba Thaw

Lopez, 39, has been waiting for this day for the better part of the past decade.

“Vindicated is certainly one of the things that I feel," he said from his Coral Gables, Florida, office, decorated with paintings depicting the Cuban diaspora experience, his collection of busts of the Cuban poet Jose Marti, and his cigar humidor. (He prefers Romeo y Julieta, a brand nationalized by Cuba but later replicated in exile.)

“It’s just intensely personal, having come from a Cuban family, political prisoners," said Lopez, whose great uncle Mario Chanes de Armas was held about three decades in one of Castro’s prisons.

Unused Weapon

Indeed, thousands of families have stories of assets lost when they fled under Castro’s threats. The ability to sue might provide them a semblance of long-awaited justice. But there could be collateral damage to key U.S. relationships. The Helms-Burton Act of 1996 created the legal recourse. Yet until Trump, every president has delayed implementation of the lawsuit provision, due in large part to concerns that the cases would bedevil global corporations and leave the U.S. at odds with allies.

The current administration appears to have decided it’s worth the risk. As some progressive Democrats embraced the term socialism, Trump has sought to make an example of Cuba during speeches in Florida, America’s biggest swing state and the seat of the island nation’s exile community.

Now, the administration is blaming Cuba for backing Venezuela’s autocratic President Nicolas Maduro and thwarting opposition leader Juan Guaido’s efforts to unseat him. Trump suggests Cuba props up Maduro amid food and medicine shortages, rigged elections and growing discontent in the streets. He tweeted Tuesday that he may implement a "full and complete" embargo on Cuba, beyond what’s already in place, in retaliation for its military presence in Venezuela.

The State Department didn’t immediately respond Wednesday to a request for comment on impending lawsuits.

Nor did Cuba’s government. But this month, Josefina Vidal -- Cuba’s ambassador to Canada and the negotiator who normalized relations with the U.S. during the Obama years -- said America had exaggerated Cuban influence in Venezuela. She also said the Trump approach wouldn’t do anything to remove the regime in Havana.

Expired Time

For years, there was an effort to settle many of the claims, and such a negotiated deal was seen as a necessary precursor to further rapprochement -- including an eventual lifting of the U.S. embargo.

The Obama administration dallied because it failed to anticipate Trump’s defeat of Democrat Hillary Clinton, said John Kavulich, president of the New York-based Trade and Economic Council, which acts as a liaison for companies interested in doing business on the island. The group officially takes no political positions, but its web site displayed a countdown clock to the opening of the lawsuit window.

Kavulich said he was surprised that Trump, who trumpets his deal-making prowess, hadn’t attempted a compromise.

“That one’s a pretty easy one,” he said. “It’s a real-estate settlement. This has now left the political process and moved into the judicial process.”

Lost Land

For Lopez, one of the first filings will be for the woman who appeared at his office not long ago and matter-of-factly produced from a plastic supermarket bag the 1903 parchment deed to a massive sugar plantation.

But he acknowledges that many challenges lie ahead, including actually collecting any awards. He also questioned whether inherited property claims will be permitted to proceed.

“What happens if you inherit the claim when your father passes away and leaves you this deed, this proof of ownership, but he died in 2010?" Lopez said. "The purpose of the Helms-Burton Act is to help get a remedy for the people that had their property stolen. If you go by a strict interpretation, thousands and thousands of people will be out of luck because their parents died.”

Under Trump, U.S. policy toward Cuba is undergoing a remarkable reversal. In 2015, America reopened its Havana embassy after decades of post-revolutionary diplomatic silence. The next year, Barack Obama became the first president to visit the city since Castro took power, promoting warming relations and heralding a potential rollback of the decades-old embargo.

U.S. economic policy had failed to achieve the goal of forcing Castro and his brother, Raul, from power, but many Cuban-Americans blasted the new approach as too soft on a brutal, anti-democratic regime.

Lopez said he hopes Trump keeps ratcheting up the pressure.

“These are foreign companies that are going to be held accountable, but the Cuban government still hasn’t," he said. "That shoe hasn’t dropped yet, and that shoe needs to drop."

--With assistance from Stephen Wicary.

To contact the reporter on this story: Jonathan Levin in Miami at jlevin20@bloomberg.net

To contact the editors responsible for this story: Michael J. Moore at mmoore55@bloomberg.net, Stephen Merelman, Flynn McRoberts

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