One of the major determinants of the length of a project for a medical device would be whether the goal is to obtain a 510(k) clearance or a PMA. To obtain a 510(k) it is only necessary to demonstrate that a device is substantially equivalent to a device that was developed before 1976 (when the Medical Device Ammendments went into effect granting the FDA authority over medical devices) or a device that is already approved as a Class II device. A PMA needs to demonstrate safety and efficacy, with support using clinical data via a clinical trial. This is obviously much harder, takes longer, and is more expensive to complete compared to a 510(k), and as a result many companies will try to get new devices cleared as via a path of substantial equivalence. My question is how far can you embellish how similar a new device is to a predicate device? What ethical responsibilities lie with the company when they take this risk? Given that fraudulent 510(k) notices are a felony offense, this issue is taken very seriously with the FDA.