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I-129 Nonimmigrant Worker Petitions — H-1B Portability and Its Limits

I-129 covers many distinct nonimmigrant worker classifications — H-1B, L-1, O-1, TN, E-1/E-2, R-1, P-1, and others — which behave differently under the hood; never assume which classification a case is without it being independently confirmed.

Published

2026-01-01

Summary

I-129 covers many distinct nonimmigrant worker classifications — H-1B, L-1, O-1, TN, E-1/E-2, R-1, P-1, and others — which behave differently under the hood; never assume which classification a case is without it being independently confirmed. For H-1B specifically, AC21 portability means someone can generally start working for a new employer as soon as a new or transfer I-129 petition is properly filed and receipted, not upon approval — provided they're maintaining valid H-1B status (or within the 60-day post-employment grace period), the new employer has a certified Labor Condition Application and is paying prevailing wage, and there's no history of unauthorized work.

Current status

If the new petition is later denied, work authorization under it ends immediately — this is a real, high-stakes fact that should never be softened or left implied when portability comes up.

Read the primary source ↗

Source: H-1B Transfer and Portability Under AC21

General policy background, not a diagnosis of any specific case — CaseWhy's own case status API never confirms why a case is delayed. For guidance specific to your case, talk to a licensed immigration attorney.

I-129 Nonimmigrant Worker Petitions — H-1B Portability and Its Limits, Explained | CaseWhy