March 9 – Prior to 4:00 p.m., New York time, clubs must exercise options for 2017 on all players who have option clauses in their 2016 contracts.
March 9 – All 2016 player contracts will expire at 4:00 p.m., New York time.
March 9 – The 2017 league year and free agency period begin at 4:00 p.m., New York time.
March 9 – Trading period for 2017 begins at 4:00 p.m., New York time after expiration of all 2016 contracts.
http://www.raiders.com/news/article-1/NFL-Announces-List-Of-Important-Dates-For-2017/16803ca0-0d4d-4f3c-ad91-0b28a4bc4e46