AN OPEN LETTER TO CHARLES RIVER LABORATORIES INCOMING CEO BIRGIT GIRSHICK Dear Ms. Girshick, My name is Chip. I am a dog walker from Sterling, Massachusetts — twenty minutes from your facility at 55–57 Union Street in Worcester. I am not a scientist. I am not a lobbyist. I am just a man who loves animals. l was troubled recently when I found out what was happening to dogs and other animals inside this location just a short drive from my front door. As someone who believes that all animal testing should end entirely, I believe that you and your company are in a unique position to help make that change possible. You are stepping into leadership at a historic inflection point — not just for Charles River, but for science itself. The FDA Modernization Act 2.0 has opened the door. NAMs — organ-on-a-chip systems, organoids, AI-driven in silico modeling — are no longer aspirational. They are here, they are validated, and study after study demonstrates they outperform animal models in predicting human outcomes. The science has moved. The law has moved. The moral consensus of the American public has moved. The only question is whether Charles River will lead that movement — or be overtaken by it. I am begging you to seize this moment. Commit Charles River to ending all animal testing by the close of 2026. Retrain your workforce in NAMs. Not one job need be lost — the same talented people who maintain animal colonies today can become the technicians and specialists running the most advanced testing platforms on earth. Worcester, Massachusetts could become the center of a new scientific revolution. A long overdue evolution. That is not hyperbole. This is a genuine generational opportunity sitting in your hands on the first day of your tenure. And with that larger vision, I ask something smaller and more immediate — something that would cost Charles River very little and mean everything to the animals and the people who love them. Please end all canine experiments immediately, company wide. Today. Stop all experiments underway and cancel any pending ones. Adopt out every current research dog currently undergoing experiments or waiting to undergo experiments. And please, please sever your ties with Ridglan Farms and Marshall BioResources immediately. Those relationships are a reputational anchor dragging Charles River toward the wrong side of history. It can start with the dogs at 55–57 Union Street in Worcester. I have driven past that building many times. I know those dogs are there. That is not an abstraction to me — it is a daily ache. I am asking you, person to person, to let them go. But Worcester must only be the beginning. I urge you to commit, publicly and immediately, to ending all animal testing and freeing all dogs and cats and indeed all animals held across every Charles River facility and subsidiary worldwide and immediately begin to rapidly transition each site to NAMs before the close of 2026. Start in Worcester, prove it can be done, and then carry that model to Edinburgh, to Mattawan, to Reno, to Montreal, to every building on every continent that bears the Charles River name. The infrastructure is there. The science is ready. All that is needed is the will of one leader willing to make history. You have inherited a company with extraordinary scientific talent, deep institutional knowledge, and the infrastructure to pivot. Jim Foster built something formidable over fifty years. You now have the chance to build something transcendent — a Charles River that doesn't merely serve the future of medicine but defines it, without a single animal having to suffer for it. The reputational repair alone would be staggering. The goodwill, the press, the public trust — these are not small things for a publicly traded company navigating a skeptical world. But more than strategy, more than brand — this is simply the right thing to do. I am one solitary citizen and animal lover. But I believe ordinary people still have the right to ask great things of powerful, influential institutions. I am asking. With hope and respect, your neighbor Chip