Columbus City Attorney Zach Klein is taking the Trump administration back to federal court, unveiling a new lawsuit on Friday, June 5, 2026, that targets a Centers for Medicare and Medicaid Services rule his office says would hike costs and knock people off Affordable Care Act exchange coverage. Klein is pitching the case as a defense of working families and city budgets against what he calls an unlawful rewrite of marketplace rules, even as other ACA changes from the administration continue to trigger lawsuits around the country.
“Every American deserves quality, affordable healthcare,” Klein said in a statement, warning that the rule would raise premiums and push people out of exchange plans. As reported by WSYX/ABC6, the city is calling this its third lawsuit over the administration’s ACA policy changes and, according to the news release, the 10th lawsuit Klein has filed during the president’s second term.
What the CMS Rule Would Change
The contested rule is part of CMS’s Notice of Benefit and Payment Parameters for 2027, a package of marketplace regulations that would tighten eligibility verification, expand plan design flexibility, and alter some subsidy and enrollment provisions. CMS says the goal is to crack down on improper enrollments and bring premiums down for consumers. Critics counter that the very same tweaks would water down benefit standards and drive up out-of-pocket costs for people who rely on ACA coverage. For the agency’s own description of the proposals, see CMS.
How Big the Impact Could Be
Klein’s office argues the rule would lead to higher premiums and patient expenses and could strip coverage from millions of people who buy insurance on the exchanges. The city’s release attached to the complaint estimates that more than 2.2 million people could feel the impact of the change, according to the City of Columbus.
Independent reporting and court filings have landed in roughly the same ballpark, projecting effects in the high millions for marketplace enrollees nationwide. Similar estimates are detailed by Healthcare Finance News.
Courts Already Pushed Back
The Columbus case is not starting from a blank slate. A federal judge in Maryland already curbed parts of the administration’s 2025 Marketplace Integrity and Affordability rule, issuing a preliminary injunction in August 2025 that blocked several provisions while litigation continues. In that decision, the court found that the plaintiffs were likely to prevail on key Administrative Procedure Act claims and ordered portions of the rule paused before they could take effect. The memorandum opinion is available at Justia.
Legal Path Ahead
The Columbus complaint asks the court for both declaratory and injunctive relief under the Administrative Procedure Act, arguing that CMS exceeded its statutory authority and acted in an arbitrary and capricious way when it finalized the rule. The suit lines up with a broader coalition that has included other cities and health care organizations, along with public-interest lawyers who have appeared in earlier ACA marketplace challenges, according to the Georgetown Litigation Tracker.
For more details on the plaintiffs’ briefs and supporting declarations in the Columbus case, see the filing from the City of Columbus.
“Rolling back that access is un-American,” Klein said, urging the courts to keep existing marketplace protections in place while the challenge plays out. The lawsuit adds another test of how far the administration can go in reshaping ACA exchanges, setting the stage for a federal court fight that will unfold over the coming months.
