The H-1B temporary worker visa classification is designated for individuals coming to the U.S. to perform services in a specialty occupation.
Specialty occupation is defined as "an occupation which requires theoretical and practical application of a body of highly specialized knowledge, and attainment of a bachelor's or higher degree for the specific specialization (or its equivalent in experience)." (Immigration and Nationality Act 214(i))
The H-1B is employer-specific, meaning the H-1B beneficiary must be an employee of the H-1B petitioning employer, and may only receive compensation from that employer.
Immigration regulations limit the total number of new H-1B petitions issued each year to private, for-profit companies, but institutions of higher education and certain non-profit organizations are currently exempt from this cap.
H-1B visa holders are eligible for a total maximum stay of six years. The six-year limit includes any time spent at another institution or company. A new six-year period may begin only after the beneficiary has spent at least one year outside of the United States. There are limited provisions to extend the six-year maximum period of stay for H-1B beneficiaries in the permanent residence process.
An initial H-1B petition may request a validity period of up to three years at one time.