Significant Victory for Analysis Group Clients in LIBOR Antitrust Class Action

December 3, 2025

In a high-profile and long-running antitrust case, Analysis Group was retained by the defense on behalf of major banks accused in a multidistrict litigation (MDL) of engaging in a horizonal price-fixing conspiracy to suppress the US Dollar London Interbank Offer Rate (LIBOR), an interest-rate benchmark. The plaintiffs – a certified class of investors who purchased LIBOR-based financial instruments during the relevant period and numerous opt-out plaintiffs – claimed that the defendants conspired to suppress (reduce) LIBOR, resulting in financial harm, including through lower interest rates on plaintiffs’ investments.

An Analysis Group team supported the work of Professor R. Glenn Hubbard who filed multiple expert reports and provided deposition testimony both on class certification issues and to rebut the analysis of the plaintiffs’ experts’ calculation of what LIBOR would have been in a “but-for” world without the defendants’ alleged conduct. Touching on an issue critical to the plaintiffs’ claim that the defendants had suppressed LIBOR, Professor Hubbard identified flaws in the plaintiffs’ experts’ economic models, including the use of an inappropriate benchmark rate to model the but-for world and the failure to appropriately consider the global financial crisis as an alternative explanation for why LIBOR diverged from that benchmark rate during the at-issue period. 

A judge in the US District Court for the Southern District of New York rejected all the plaintiffs’ claims, excluded the testimony of some of the plaintiffs’ experts, and granted the defendants’ motions to decertify the class of individual plaintiff investors and for summary judgment. The judge found that, due to the plaintiffs’ failure to establish a reliable estimate of but-for LIBOR, they “cannot establish that they suffered an injury as a result of defendants’ conduct.” Repeatedly referencing Professor Hubbard’s rebuttal critiques of the plaintiffs’ economic models, the judge rejected the plaintiffs’ allegations as “economically senseless.” In granting summary judgment, she concluded, “Having found that plaintiffs failed to proffer evidence sufficient to raise a triable issue of fact as to conspiracy and suppression, all of plaintiffs’ claims fail.”

Professor Hubbard was supported by an Analysis Group team led by Managing Principals Michael Beauregard and Marissa Ginn and Vice Presidents Alix Duhaime-Ross, Michal Popiel, Ludmila Rovba, and Andrew Stichman.