Policy frameworks for animal welfare have historically excluded invertebrates. Emerging evidence for sentience in insects, cephalopods, and crustaceans is driving policy evolution.
The policy exclusion of invertebrates from welfare protection has been based on assumptions of their limited sentience that science is actively revising. Cephalopods and decapod crustaceans now have strong evidence for nociception and pain behavior. Insect sentience remains more uncertain but the scale of insect farming — potentially trillions of individuals — means even small probabilities of suffering have enormous welfare stakes. Policy responses are beginning to develop but lag far behind the scientific evidence.