This is an interesting discussion topic! In the medical device industry, it is very critical to have the most up to date DHF as the project moves forward with different phases. Many medical device companies have internal audit program, part of the quality system that can help the company identify any gaps and remediate immediately. If the company does not have the internal audit program set up, it is usually outsourced to a third party auditor. Furthermore, any ISO 13485 certified company has an annual surveillance audit, which also helps prepare the company for FDA audit. Any time there is change of any documentation within the DHF, the company must follow their document control procedure for traceability purposes. In this way, the DHF will be updated at all times following the FDA and the ISO regulations and will be audit ready.