The FDA denied Harrison.ai’s petition seeking a partial 510(k) exemption for certain diagnostic and detection AI devices. The agency’s decision maintains the existing premarket review pathway unless the manufacturer has 510(k) clearance for a similar device category and submits a robust postmarket plan. The ruling reinforces that regulatory flexibilities for AI-enabled medical software will remain constrained without demonstrated equivalence and ongoing safety monitoring. For developers, the outcome increases the likelihood that AI diagnostic platforms will need to stay within standard review frameworks even when device functionality overlaps with cleared products. The FDA action also signals the regulator’s continued emphasis on postmarket performance evidence for AI systems that evolve through analytical and operational inputs.