"Facing a CDC investigation tying an E. coli outbreak to its Quarter Pounders, the company has been linked to 75 cases across 13 states (including one death and 22 hospitalizations), with most cases in Colorado and Nebraska; a Colorado customer has filed a lawsuit alleging product liability, negligence, and breach of implied warranties. Officials have focused on the fresh slivered onions used on the Quarter Pounder—sourced from a single supplier—after the Colorado-based Taylor Farms recalled yellow onions; major distributors Sysco and US Foods warned customers to stop using Taylor Farms (also sold as Cross Valley Farms) onions, and several other national chains pulled onions from menus. The chain briefly stopped selling the Quarter Pounder in affected states but resumed sales after its patties tested negative for E. coli. The episode follows prior foodborne incidents tied to the company (2008 tomatoes/salmonella, 2018 cyclospora from salads, 2022 E. coli in chicken nuggets) and has dented its stock, though long-term effects remain uncertain." - Bettina Makalintal