Veteran Traders Sue CME Over Electronic Trading Shift

On Monday, July 7, 2025, a significant legal battle is set to commence in Chicago as veteran traders from the Chicago Mercantile Exchange (CME) and the Chicago Board of Trade (CBOT) initiate a class action lawsuit against the exchange operator. The case will be heard by Cook County Circuit Judge Patrick J. Sherlock at the Richard J. Daley Center, with opening statements scheduled between 9:30 and 10:30 AM ET.

The lawsuit, brought forth by a group of experienced traders, alleges that CME Group’s transition to electronic trading over a decade ago infringed upon their contractual rights as members. This shift, they claim, has resulted in both financial and professional losses. The case also raises questions about CME’s 2012 relocation of its primary electronic trading platform from the Chicago floor to a data center in Aurora, a suburb west of the city.

According to court documents, the plaintiffs, who are certified classes of Class B shareholders in CME Group and certain members of its CBOT subsidiary, assert that the changes violated membership privileges. These privileges included reduced trading fees and exclusive access to specific trading functions. The lawsuit highlights instances where non-members using the Aurora system were charged lower fees than members, thereby eliminating one of the key financial benefits of membership.

Judge Sherlock denied CME’s request to dismiss the case in an April 15 order, stating that the plaintiffs had raised substantial legal and factual questions. “The Court found an issue of disputed fact concerning almost every point defendants made in their brief in support of summary judgment,” Sherlock wrote. While acknowledging that CME has a defensible case, he concluded that a jury must decide the outcome. If the jury finds CME guilty, the exchange could face over $1 billion in damages. Attorney Steve Morrissey of Susman Godfrey, representing the plaintiffs, noted that CME has attempted to delay the case, trying to get it dismissed multiple times.

The value of CME memberships has significantly declined since 2007, when they were worth over $1 million. Today, they are valued at significantly less. On April 2, 2025, a CME membership last sold for $700,000, down from the $1.5 million peak in 2008, according to the plaintiffs’ attorneys. For many traders, these memberships are considered “family legacies,” often passed down through generations. The plaintiffs argue that by moving the trading floor to Aurora and removing membership benefits, CME devalued what they viewed as heirlooms.

CME maintains that the rights and privileges associated with floor trading are still intact. However, Chicago traders contend that screen-based platforms have caused liquidity on the trading floors to plummet, effectively ending the era of shouting brokers and hand signals in Chicago’s pits. Attorney Morrissey stated that the plaintiffs would seek damages tied to the lost value of exclusive trading rights. “There’s the damage number for the value of the exclusivity right that members haven’t enjoyed for the past decade,” he said. Additional damages would be limited to the individual memberships within the class.

Beyond financial restitution, the plaintiffs seek a declaration from CME that Aurora qualifies as a trading floor. If the jury agrees, CME may be forced to revise its membership benefits and trading access structure. A ruling against CME could also compel corporate members using single memberships to provide access to multiple traders, potentially at high costs under a revised membership structure. Furthermore, the unresolved litigation could hinder any potential merger talks involving CME, as sources close to the case suggest that the dispute may deter Cboe Global Markets from entering negotiations, especially if the stock is involved in the deal.