An L-1 visa is a visa document used to enter the United States for the purpose of work in L-1 status. It is a non-immigrant visa, and is valid for a relatively short amount of time, from three months (for Iran nationals) to five years (India, Japan, Germany), based on a reciprocity schedule. With extensions, the maximum stay is seven years. L-1 visas are available to employees of an international company with offices in both the United States and abroad. The visa allows such foreign workers to relocate to the corporation's US office after having worked abroad for the company for at least one continuous year within the previous three prior to admission in the US. The US and non-US employers must be related in one of four ways: parent and subsidiary; branch and headquarters; sister companies owned by a mutual parent; or 'affiliates' owned by the same or people in approximately the same percentages. The L-1 classification also enables a foreign company which does not yet have an affiliated U.S. office to send an employee to the United States to help establish one, with additional requirements. Spouses of L-1 visa holders are allowed to work without restriction in the US (using an L-2 visa), and the L-1 visa may legally be used as a stepping stone to a green card under the doctrine of dual intent. In 2010, the U.S. Citizenship and Immigration Services (USCIS) approved 74,719 L-1 visas, out of 91,086 applications (a refusal rate of 18%).