An anti-corruption watchdog celebrated Friday after a federal court reopened a suit alleging President Donald Trump routinely violates the U.S. Constitution's emoluments clauses and is profiting from the presidency.

The Second U.S. Circuit Court of Appeals rejected a lower court's decision to throw out the case brought by Citizens for Responsibility and Ethics in Washington (CREW) and a number of hospitality companies who argue that the president's continued involvement in his real estate empire has harmed their own businesses.

CREW filed the suit against Trump in January 2017, days after he took office and refused to divest from the Trump Organization—instead handing over management of the business to his two eldest sons and continuing to maintain financial control of his properties.

The group called the decision a "massive victory" in its fight to hold the president accountable for what it calls "unconstitutional conduct."

BREAKING: The Second Circuit Court of Appeals just revived our landmark emoluments case. We will proudly fight as long as needed to ensure Americans are represented by an ethical government under the rule of law. https://t.co/gI61SNfwbY — Citizens for Ethics (@CREWcrew) September 13, 2019

This ruling is a massive victory for CREW, in a legal fight that started on Trump’s third day in office.

It’s also the latest setback for Trump in his attempts to shut down claims that he's unconstitutionally profiting from his business interests.https://t.co/1CqzRmUZNo — Citizens for Ethics (@CREWcrew) September 13, 2019

"We never wanted to be in a position where it would be necessary to go to court to compel the president of the United States to follow the Constitution," Noah Bookbinder, executive director of CREW, said Friday. "However, President Trump left us no choice, and we will proudly fight as long as needed to ensure Americans are represented by an ethical government under the rule of law."

The emoluments clauses of the Constitution state that the president must not accept gifts or payments from foreign or domestic government officials without congressional approval.

CREW and many who own properties near Trump's hotels in New York and Washington, D.C. argue that, with Trump in the White House, it has been in foreign and domestic leaders' interest to stay in the president's hotels.

Those stays cut into others' profits, the plaintiffs say, and create unethical financial entanglements between Trump and the governments of Saudi Arabia, Kuwait, and other countries that have sent delegations to stay at the president's properties.

"Plaintiffs allege that in competing over the exact same customer base, Trump establishments secure an unlawful advantage because giving patronage to Trump establishments offers," the court wrote, "in addition to comparable services, the potential, by enriching the president, of securing his favor in governmental decisions."

As it has several times over the past two and a half years, CREW called on Trump to immediately give up control of his business empire.

"If President Trump would like to avoid the case going further and curtail the serious harms caused by his unconstitutional conduct," Bookbinder said, "now would be a good time to divest from his businesses and end his violations of the emoluments clauses of the Constitution."