This guidance will assist industry and Agency staff in determining when a software (including firmware) change to a medical device may require a manufacturer to submit and obtain FDA clearance of a new premarket notification (510(k)). This guidance is not intended to implement significant policy changes to FDA’s current thinking on when submission of a new 510(k) is required for a software change to a 510(k)-cleared device (or group of devices) or other device subject to 510(k) requirements, such as a preamendments device or a device that was granted marketing authorization via the De Novo classification process under section 513(f)(2) of the Food, Drug, and Cosmetic Act (FD&C Act) (also referred to together as “existing devices”). Rather, the intent of this guidance is to enhance the predictability, consistency, and transparency of the “when to submit” decision-making process by providing a least burdensome approach, and describing in greater detail the regulatory framework, policies, and practices underlying such a decision, specifically as it relates to software changes.