41.22—Retention of records.
All records required to be kept under this part, including copies of claims and schedules, authorizations, notices of release, reports, and returns, shall be retained for three years following the close of the year in which filed or made, or in the case of an authorization, for three years following the close of the calendar year in which the operation under such authorization is concluded. Such records shall be made available for inspection by any appropriate TTB officer upon his request.