Tax and filing requirements that result when an employee moves between states or countries. For example, an employee may be granted an award when living on one jurisdiction, vesting may occur when she is living in a different place, she may exercise stock options in another state or country, and she may sell the shares in a fourth location. Both the employee and her company will have tax, withholding, and reporting obligations that trail along as the employee moves. For more on the issues faced by mobile employees with equity awards, see FAQs on state mobility (either options or restricted stock/RSUs) and global mobility.