Two brothers from Miami pleaded guilty on Wednesday in federal court in Manhattan for their role in a nearly $23 million insider-trading scheme surrounding the 2021 announcement that former President Donald J. Trump’s social media company planned to merge with a cash-rich shell company.

Michael and Gerald Shvartsman, who had pleaded not guilty to securities fraud charges last summer, were set to go on trial later this month. But the brothers decided this week to forgo a trial, instead entering their guilty pleas before Judge Lewis J. Liman of U.S. District Court for the Southern District of New York.

Each man pleaded guilty to one count of securities fraud.

Michael Shvartsman, according to federal prosecutors, was the mastermind of the scheme to profit from the announcement, in October 2021, that Trump Media & Technology Group planned to merge with Digital World Acquisition Corporation, a shell company that had just raised $300 million in an initial public offering. The authorities charged Michael Shvartsman, 53, a Miami financier, with making $18.2 million in illicit trading profits; and his brother, 46, who owns an outdoor furnishing store in Miami, with raking in $4.6 million.

Michael Shvartsman, who ran a venture investment firm called Rocket One, used some of the proceeds from the scheme to buy a $14 million luxury yacht that he named Provocateur.

The brothers each face prison sentences of up to 20 years. Their plea agreements with the government recommend a sentence of roughly four to five years for Michael Shvartsman; and three to four years for Gerald Shvartsman.

Judge Liman, who is not bound by those recommendations, set sentencing for both men for July 17.

The brothers are Canadian citizens and could face deportation at the end of their sentences.

Gerald Shvartsman told Judge Liman that what he did was wrong and “I will pay dearly for it for the rest of my life.” His brother told the judge, “I understand these trades were unlawful.”

As part of their plea agreements, the brothers agreed to forfeit their trading gains, and Michael Shvartsman will hand over his yacht to the government.

A third man charged in the scheme, Bruce Garelick, who had worked at Rocket One, is scheduled to go to trial at the end of the month. The authorities have said that he made less than $50,000 but was critical in giving the brothers nonpublic inside information about the merger talks between Trump Media and Digital World.

Mr. Garelick, a former hedge fund manager, became a board member of Digital World before it went public but after Rocket One had become an investor. A lawyer for Mr. Garelick did not respond to a request for comment.

Trump Media, the parent company of the social media platform Truth Social, completed its merger with Digital World a little over a week ago. The deal has added billions of dollars to Mr. Trump’s net worth and boosted the market valuation of Trump Media even though it lost $58 million last year and took in just $4.l million in advertising on Truth Social.

The federal authorities investigated a handful of other people who were friendly with the Shvartsmans and had made millions of dollars in profitable trades around the time of the merger announcement, according to court filings, but none were charged with wrongdoing or found to have ties to anyone associated with Trump Media.

No one from Trump Media was charged with any wrongdoing, either. The insider-trading investigation contributed to a more than two-year delay in completing the merger. The deal was also held up by a Securities and Exchange Commission investigation into inappropriate merger talks between the companies that was resolved last summer, with Digital World agreeing to pay an $18 million fine.