WASHINGTON — One month after Neil M. Gorsuch was appointed to the Supreme Court in April 2017, he and two partners finally sold a vacation property they had been trying to offload for nearly two years. But when he reported the sale the next year, he left blank a field asking the identity of the buyer.

County real estate records in Colorado show that Brian L. Duffy, the chief executive of Greenberg Traurig, a sprawling law firm that frequently has business before the court, and his wife, Kari Duffy, bought the property.

The buyer’s identity — and Justice Gorsuch’s decision not to disclose it — was reported earlier on Tuesday by Politico. The revelation comes as scrutiny on Supreme Court ethics and financial entanglements has intensified, prompting Democratic lawmakers to call for tightening the rules for justices.

ProPublica reported this month that Justice Clarence Thomas had not disclosed that he had repeatedly received free travel for lavish vacations and other purposes from a Republican megadonor, Harlan Crow, and that he had sold properties to Mr. Crow in Georgia.

Justice Gorsuch did not break the law by omitting the buyer’s identity, said Stephen Gillers, a New York University professor and specialist in legal ethics. Under a 1978 statute governing financial disclosures, federal judges are not required to disclose who bought property from them.

Gabe Roth, the executive director of Fix the Court, a nonpartisan group that presses for greater transparency and accountability by the justices, agreed that the omission did not violate the law. But he argued that Congress should pass legislation expanding what justices must disclose, including losses from any sales, the nature of partnerships that hold real estate and who buyers are.

Senator Richard J. Durbin, Democrat of Illinois who leads the Judiciary Committee, said in a statement that the panel planned to scrutinize potential ethics reform legislation for the Supreme Court.

“We have seen a steady stream of revelations regarding Supreme Court justices falling short of the ethical standards expected of other federal judges and of public servants,” he said. “The need for Supreme Court ethics reform is clear, and if the court does not take adequate action, Congress must.”

The Supreme Court press office did not respond to a request for comment from Justice Gorsuch.

Greenberg Traurig employs about 2,650 lawyers across 45 locations in the world and reported over $2 billion in revenue in 2021, according to its website.

A search of the Supreme Court docket on the legal research site Nexis returned more than four dozen cases involving lawyers from the firm from when Justice Gorsuch was appointed to the end of 2022, the latest date in the database. They included cases the court took up, petitions in which it declined to hear an appeal, and friend-of-the-court briefs submitted in cases in which the firm did not represent a litigant.

Mr. Duffy, who lives in Colorado, did not respond to an email from The New York Times. But he told Politico that he bought the property because he is a fly fisherman and that he has never argued before Justice Gorsuch or met him socially. He also said he did not know that the jurist had a stake in the property when he made his first offer.

It is not clear when that offer was made. The New York Times described the justice’s ownership in the property in a March 2017 article that detailed his ties to the billionaire Philip F. Anschutz.

Mr. Anschutz, a major conservative donor, lobbied Colorado’s lone Republican senator and the George W. Bush administration to nominate Mr. Gorsuch to an appeals court seat in 2006. The 40-acre property that Mr. Duffy eventually bought was another link between the jurist and the mogul.

In 2005, Justice Gorsuch had joined with two top lieutenants to Mr. Anschutz to form a limited liability company to acquire the land.

Calling themselves the Walden Group, they bought the property for $900,000, property records show, and built a 2,923-square-foot log house for fishing vacations. It included 2,000 feet on both sides of the Colorado River. The venture was structured as a time share, giving each partner a right to use it a certain number of days.

In 2017, a spokeswoman for Justice Gorsuch told The Times that he had contributed $360,000 to the Walden Group, giving him a 20 percent stake; the two lieutenants of Mr. Anschutz each contributed twice as much and owned 40 percent.

While Justice Gorsuch contributed the least money, county records directed any correspondence about the property to him at the federal courthouse in Denver.

In 2015, Justice Gorsuch and his partners began trying to sell the property. They originally listed it that July for $2,495,000, a real estate listing shows. They reduced the price several times before Mr. Duffy and his wife bought it in May 2017 for $1,825,000, county records show.

On his financial disclosure form the next year, Justice Gorsuch reported the transaction on the 56th line in the middle of 113 investment matters, most of which appeared to be stocks, bonds or dividends.

He was terse, writing “Walden Group LLC” in a column that sought a description of the asset, and he did not explain what it was or mention real estate. He valued the transaction from $250,001 to $500,000, and left empty a field asking him to list the “identity of buyer/seller (if private transaction).”

Justice Gorsuch did not report any income from the sale, and it appears that he about broke even on it.

Mr. Roth said the episode showed that justices should be required to be more forthcoming in their annual reports.

“There are examples of justices omitting these types of transactions, but even when they include them, the public has every right to know more about it,” he said. “It’s hard to do basic oversight without knowing who is on the other side of the transaction.”

Kitty Bennett contributed research.