49 CFR §831.64

1. (a)General. Any party to an investigation designated under § 831.61 may submit to the NTSB written proposed findings to be drawn from the evidence produced during the course of the investigation, a proposed probable cause, and/or proposed safety recommendation(s) designed to prevent future major marine casualties and marine casualties.
2. (b)Timing of submissions. The IIC will inform parties when submissions are due. All written submissions must be received by the due date. If there is a Board meeting, the due date will be set prior to the date the matter is published in the Federal Register.