Certain Restricted Stock Units of AK Steel Holding Corporation are subject to a Lock-Up Agreement Ending on 24-JAN-2017. These Restricted Stock Units will be under lockup for 90 days starting from 26-OCT-2016 to 24-JAN-2017. Details: The directors and executive officers have entered into lock-up agreements with the underwriters, may not offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, or otherwise transfer or dispose of, directly or indirectly, any shares of common stock or any securities convertible into or exercisable or exchangeable for common stock, during the period beginning on the date of the prospectus supplement and ending 90 days after the date of the prospectus supplement, may not, without the prior written consent of the representatives.