FN11.   H-1B portability has limitations.  A provision unique to H-1B extensions allows the employee to work for 240 days while awaiting approval of the new employer’s H-1B petition, with no adverse immigration consequences.  But, if USCIS ultimately denies the H-1B application, the employee will be deemed to have been “out of status” during the 240 days, and must immediately leave the country.  While this “innocent” overstay is not be a bar to re-entry, it will always be an issue listed in the employee’s immigration history, and will cause inevitable delays during the employee’s consular processing and return from international travel.