Online brokers charge a assignment fee to clients who have the stock from an option automatically sold or bought due to the option they were holding being exercised.
The term assignment is defined as (source thinkorswim), "Assignment is the term used when someone who is short a call or put is forced to sell (in the case of the call) or buy (in the case of a put) the stock. Remember, for every option trade there is a buyer and a seller, so if you are short an option, there is someone out there who is long that option and who could exercise."
A list of the option assignment fees charged by every one online brokerage are listed below.
Published on Monday, June 27th, 2016 .