H-1B

The H-1B is a non-immigrant visa in the United States under the Immigration and Nationality Act, section 101(a)(17)(H). It allows U.S. employers to temporarily employ foreign workers in specialty occupations. If a foreign worker in H-1B status quits or is dismissed from the sponsoring employer, the worker must either apply for and be granted a change of status to another non-immigrant status, find another employer (subject to application for adjustment of status and/or change of visa), or leave the U.S. Effective January 17, 2017, USCIS modified the rules to allow a grace period of up to 60 days.

The regulations define a "specialty occupation" as requiring theoretical and practical application of a body of highly specialized knowledge in a field of human endeavor including but not limited to biotechnology, chemistry, architecture, engineering, mathematics, physical sciences, social sciences, medicine and health, education, law, accounting, business specialties, theology, and the arts, and requiring the attainment of a bachelor's degree or its equivalent as a minimum (with the exception of fashion models, who must be "of distinguished merit and ability"). Likewise, the foreign worker must possess at least a bachelor's degree or its equivalent and state licensure, if required to practice in that field. H-1B work-authorization is strictly limited to employment by the sponsoring employer.

On March 3, 2017 the U.S. Citizenship and Immigration Service announced on their website that starting from April 3, 2017 they will temporarily suspend premium processing for all H-1B visa petitions until further notice.

The duration of stay is three years, extendable to six years. An exception to maximum length of stay applies in certain circumstances:

A time increment of less than three years has sometimes applied to citizens of specific countries. For example, during her time as an H-1B visa holder, Melania Trump was limited to one year increments, which was the maximum time allowed then per H-1B visa for citizens of Slovenia, which Melania Trump was then a citizen of.

H-1B holders who want to continue to work in the U.S. after six years, but who have not obtained permanent residency status, must remain outside of the U.S. for one year before reapplying for another H-1B visa if they do not qualify for one of the exceptions noted above allowing for extensions beyond six years. Despite a limit on length of stay, no requirement exists that the individual remain for any period in the job the visa was originally issued for. This is known as H-1B portability or transfer, provided the new employer sponsors another H-1B visa, which may or may not be subjected to the quota. Under current law, H-1B visa has no stipulated grace period in the event the employer-employee relationship ceases to exist.

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Wikipedia