Plaintiffs seek damages and injunctive relief. The lawsuit, Langer, et al. v. CME Group, Inc., et al., No. 2014 CH 00829, was filed on January 15, 2014 and is currently pending in the Circuit Court of Cook County, Illinois, Chancery Division., A trial is to begin in a long-running lawsuit by Chicago traders who say they were harmed by the exchange’s launch of electronic markets., The July 7, 2025 trial of Langer v. CME Group, Inc. marks a pivotal moment for the world's largest derivatives exchange. At stake is not only $1.3 billion in potential damages but also the very structure of CME's membership model and its ability to navigate an increasingly digitized marketplace. For institutional investors, the risks are stark: a ruling against CME could trigger financial , Plaintiffs alleged that CME Group breached their contractual obligations by requiring Class B members to pay monthly colocation fees of $8,000 to $12,000 to access the Globex platform from the Aurora facility, when previously such access had been provided at no additional charge as part of their membership rights., Longtime CME traders who claim the move to electronic trading cost them money are finally slated to get their day in court after a judge denied the exchange operator’s bid to shut down their, Lead plaintiff Sheldon Langer filed a class action against CME Group, and the Board of Trade of the City of Chicago, in Cook County Chancery Court..