By Patrick Thomas and Dave Michaels

On Dec. 19, 2022, executives from America's three biggest egg producers got on a call. The subject: how to keep the price of eggs high.

With Christmas a few days away, the chief executive of Arizona-based Hickman's Egg Ranch had an idea for how to push an industry benchmark for eggs higher, according to the Justice Department.

If Hickman's and other big egg companies all bid aggressively for eggs on a wholesale market exchange, they could raise a key pricing measure that influences the prices shoppers pay in grocery stores.

"As a group we need to bid like they vote in Chicago, early and often," an alleged co-conspirator said, according to a federal court complaint made public this week.

The complaint, filed in Iowa federal court, described a yearslong effort by a handful of major egg producers to manipulate a little-known process that helps determine what Americans pay for eggs. From 2022 to 2025, antitrust enforcers said, executives of Cal-Maine Foods, Hickman's and Versova spoke by phone and exchanged messages to coordinate bids and trading.

The effort occurred during a period when eggs were scarce, consumers paid more for cartons than ever before, and President Trump raised the issue on the campaign trail. Egg producers have blamed a historic avian flu outbreak that decimated the hen population.

Following the Hickman CEO's late-2022 message, Cal-Maine, Versova, and Hickman's collectively submitted dozens of bids to a wholesale egg marketplace known as the Egg Clearinghouse, the Justice Department alleged. Over several days, executives exchanged a flurry of messages and entered more bids. The price benchmarker, Urner Barry, then raised its egg price quotations for "white, large, shell eggs" across all regions.

On Dec. 22, 2022, the Hickman's CEO sent his fellow executives an Urner Barry report saying that egg prices were hitting records, according to the complaint. He added: "Great job in the northwest today!"

Glenn Hickman, who was CEO of Hickman's Egg Ranch up until selling the company late last year, declined to comment.

For consumers, egg prices at the time were already surging to record highs. An avian influenza outbreak had killed tens of millions of chickens and turkeys, and wholesale prices of Midwest large eggs hit $5.36 a dozen in late 2022. Egg prices climbed further in 2024 and 2025 while outbreaks continued, prompting panic buying and purchasing limits at supermarkets and egg surcharges at restaurants.

Mississippi-based Cal-Maine is the largest U.S. egg company, supplying more than 15 billion eggs each year. Versova is routinely estimated in the top five, while Hickman's is much smaller. Antitrust enforcers allege the companies' coordination was enough to game the wholesale egg trade.

Cal-Maine denied wrongdoing. It said the communications cited in the Justice Department complaint — attributed to an unnamed former employee — didn't affect egg prices, and that the company's conduct was lawful and supported the market.

Versova denied wrongdoing and said that settling the allegations allows the Iowa-based company to focus on its business. Hickman, now owned by meatpacking giant JBS and Brazilian egg supplier Mantiqueira, said the alleged conduct predated their late-2025 acquisition of the company, but that the settlement resolves all allegations.

The investigation portrayed a side of the egg business that few consumers ever encounter: an esoteric trading system built around an online marketplace that antitrust enforcers said could be manipulated by sharp traders.

Instead of producing all the eggs they sell, egg companies often purchase eggs from other suppliers on the Egg Clearinghouse, nicknamed "The Wall Street of Eggs." Pricing and trade data from the platform are used by Urner Barry, now called Expana, to set industry benchmark prices.

Contracts between egg suppliers and grocery stores are typically based on Urner Barry prices. Urner Barry's numbers impact what grocers pay for eggs and can factor into price tags for consumers.

The Justice Department complaint suggested that executives used spoofing-like tactics — a bluffing strategy in which a trader places buy or sell orders hoping to move a price, but cancels many of the orders before they are filled.

During the December 2022 episode, according to the complaint, a Versova executive placed bids for eggs in the Northwest at a couple of cents above the Urner Barry benchmark price. Once other companies began offering to sell the eggs to Versova at its higher bid, another Versova executive advised deleting the bids.

Representatives from Egg Clearinghouse and Expana didn't respond to requests for comment.

In December 2024, when egg prices started ticking up after a new round of bird flu cases, Hickman's CEO got a text from Cal-Maine's former CEO, saying, "Let it rip." The companies started submitting more bids to the Egg Clearinghouse at premium prices, which went unfilled, according to the complaint.

Executives then lobbied Urner Barry throughout the 2024 holiday season, the Justice Department said, asking the market research firm for ever-higher price quotations and to pay less attention to other companies' bids.

The Justice Department alleged that quoted prices dropped significantly from their early 2025 peaks after the federal investigation became public in March, and the companies were told to preserve any documents that could become evidence.

The price declines also followed a sharp drop in bird flu cases, giving companies time to rebuild flocks as consumer demand waned.

Cal-Maine, Hickman's and Versova agreed to settle the civil claims by collectively donating more than 50 million eggs to food banks and paying $3.3 million to New York and other states that investigated the alleged misconduct, according to court records. The deal requires court approval.

Write to Patrick Thomas at patrick.thomas@wsj.com and Dave Michaels at dave.michaels@wsj.com