The country’s biggest apartment landlords have been added to a lawsuit filed by the Department of Justice last year — which is considered “one of the most sweeping legal actions ever taken by the federal government against a private company in the rental-housing industry,” according to the Wall Street Journal.Per the report, the agency has added six prominent landlords to the suit, accusing them of using “RealPage’s rent-pricing algorithm to artificially inflate rents” across the country.“While Americans across the country struggled to afford housing, the landlords named in today’s lawsuit shared sensitive information about rental prices and used algorithms to coordinate to keep the price of rent high,” said the DOJ’s acting Assistant Attorney General of Antitrust Doha Mekki in a press release, according to WSJ.READ MORE: Trump DOJ officials may have used media leaks to interfere with 2020 election: reportThe newspaper notes, “The defendants are among the country’s largest apartment landlords and together oversee more than 1.3 million units throughout the U.S.,” according to the DOJ. One of the landlords — Greystar — rejected the department’s claims. The company, according to WSJ, “said it plans to ‘vigorously defend’ itself in the lawsuit,” while “other defendants also denied the allegations or didn’t respond to a request for comment.”READ MORE: ‘No guardrails’: Report reveals how Trump may weaponize DOJ to intimidate Congress and mediaThe WSJ’s full report is available here (subscription required).