An alien who is a specialty worker can apply for H-1B status based on a job offer from a U.S. employer. If the H-1B petition is approved, that alien can work in the United States under H-1B status.

Continued H-1B status depends on an alien holding a job with a U.S. employer. However, an alien is not bound to his or her employer for the entire duration of the relevant H-1B visa. Under what is called the H-1B portability rule, it is possible for an H-1B worker to change employers and start working for the new employer as soon as the new H-1B transfer application is filed.

The H-1B portability rule states that an H-1B worker can begin working for a new employer upon that employer’s filing an H-1B transfer petition, assuming that the alien’s previously approved H-1B remains valid. In this case, the filing date is the date USCIS receives the application—i.e., the “received date” on the receipt notice issued by USCIS.

This rule applies regardless of whether the new job is subject to the H-1B cap (see below).

It must be noted, however, that the portability provision does not confer H-1B status. It only confers the alien a right to work for the new employer while the H-1B transfer petition is pending.

There are four possible situations under which an H-1B worker can take advantage of the portability rule, depending on whether the alien’s old and new employers are cap-subject or cap-exempt.

In all four situations, the alien is able to start working for the new employer when the new H-1B petition is filed (i.e., received by USCIS).

Here are more detailed explanations of how the portability rule applies to each situation:

(1) A cap-exempt worker porting to a cap-exempt job.

Because neither job is subject to the H-1B cap, the alien can file the H-1B transfer at any time and start working for the new employer when the H-1B transfer is filed. The H-1B quota and the rush in April are irrelevant.

(2) A cap-subject worker porting to a cap-exempt job.

Because the new job is not subject to the H-1B cap, the alien can file the H-1B transfer at any time and start working for the new employer when the H-1B transfer is filed. The H-1B quota and the rush in April are irrelevant.

(3) A cap-subject worker porting to a cap-subject job.

In this situation, the alien has already taken an H-1B number; therefore, the new job doesn’t require a new H-1B number. The alien can file the H-1B transfer at any time and start working for the new employer when the H-1B transfer is filed.

(4) A cap-exempt worker porting to a cap-subject job.

In this case, the new job requires an H-1B visa number, and the alien did not obtain an H-1B visa number for his or her previous job. Therefore, the alien can file the H-1B transfer only when an H-1B visa number becomes available to him or her—that is, in April 2008. If the alien has no advanced degree obtained in the United States, he or she must file the H-1B application on April 1, 2008. If the alien has an advanced degree obtained in the United States, he or she may apply within two weeks or so of April 1.

The alien can begin working for the new employer when the H-1B transfer is filed. However, if the transfer petition is approved before the beginning of the new fiscal year (this year, October 1), the alien might not be able to continue working for the new employer between the approval date and October 1, since the alien’s H-1B will not start until October 1, 2008, and the portability rule no longer applies once the new petition is approved.

For instance, let’s say Dr. Liu is currently working as a postdoctoral researcher at a U.S. university under an H-1B visa, and she receives a job offer from a private IT company. Dr. Liu’s current job is exempt from the H-1B cap, but her new job would be subject to the cap.

At the earliest, Dr. Liu’s new employer can file her H-1B transfer petition on April 1—the first day H-1B petitions are accepted by USCIS for the fiscal year of 2009. Given the portability rule, Dr. Liu can start working for the new job immediately upon filing the H-1B petition; she doesn’t need to wait until October 1, 2008.

On the other hand, if Dr. Liu’s H-1B petition is denied for whatever reason—including a lack of available visa numbers—Dr. Liu will immediately lose the right to work for the new employer under the portability rule and will have to leave her job. Furthermore, if Dr. Liu’s H-1B petition is approved before October 1, she might have to leave her job until October 1, when she will have a valid H-1B visa number. In either situation, she would be allowed to go back to work for her old employer before October 1, 2008.

In this situation, given the limited amount of H-1B visa numbers, we would not suggest that Dr. Liu start working immediately upon filing her H-1B petition under the portability rule, unless she has an advanced degree from a university in the United States.