Your Immigration Attorney Files the H-1B. Who's Handling the I-9?

Your immigration attorney files the Form I-129. USCIS approves it. The employee gets their Form I-797. Then they show up Monday morning ready to keep working — and the question nobody answers is this: who is updating the Form I-9?

In most companies, the answer is "nobody." The attorney's engagement ends at petition approval. HR assumes immigration counsel is still on it. And the Form I-9 — the document ICE actually inspects when they show up — sits with stale information, no Supplement B, no "240-Day Ext." or "AC-21" notation, and no record of the new I-94. That is the gap that turns a routine H-1B lifecycle event into a substantive I-9 violation.

The division of labor most employers get wrong

H-1B compliance involves two parallel workflows that almost never talk to each other:

Attorneys are excellent at the left column. They are not, generally, doing the right column. They don't see your I-9s, they don't update them, and they don't track reverification dates against your HRIS. When the petition is approved or the employee ports to your company, the attorney's job ends. The employer's I-9 job is just beginning.

The five moments where I-9 errors happen on H-1B workers

Each one is a discrete employer obligation. Each one is where ICE finds substantive violations during a worksite inspection.

1. New H-1B hire (employee was outside the U.S. or just received initial H-1B approval)

Both you and the employee must complete a new Form I-9 once they begin working for you. For Section 2, the most common List A combination is the foreign passport with a Form I-94 endorsed for H-1B status with your company. Per USCIS, "If USCIS approves your petition, you will receive Form I-797, Notice of Action, which indicates that the foreign worker has been approved for H-1B classification. Once your employee begins working for you, you must both complete Form I-9."

The Form I-797 itself is not a Section 2 document. Record the I-94 and passport in List A.

2. H-1B extension of stay with the same employer (the 240-day rule)

This is where most attorney/HR handoffs break. If you file a timely Form I-129 to extend the employee's H-1B status before their current period ends, the employee is authorized to keep working for up to 240 days while USCIS processes the petition, or until USCIS decides, whichever comes first.

USCIS is explicit about what the employer must do on the I-9:

"When your employee's work authorization expires, you should write '240-Day Ext.' and enter the date you submitted Form I-129 to USCIS in the Additional Information field in Section 2. You must reverify the employee's employment authorization using Supplement B, Reverification and Rehire once you receive USCIS's decision, or by the end of the 240-day period, whichever comes first." — USCIS M-274, Section 7.5

Two things to notice:

• The notation goes in Section 2 Additional Information — not Supplement B. Supplement B comes later, when USCIS decides or the 240 days run out.
• The 240-day clock starts at the expiration of the prior H-1B status, not at the filing date.

If the petition is denied during the 240-day window, work authorization ends immediately. If the petition is approved, you complete Supplement B using the new I-94 and the original passport.

2.5 If the H-1B extension is filed late

The 240-day continuation only applies to timely extension filings — meaning USCIS received the Form I-129 before the current H-1B status expired. If the petition is filed after expiration, the employee is no longer authorized to work, and you cannot rely on the 240-day rule. This is one of the more common errors ICE flags during an inspection: the extension was filed, but it was filed late, and the employee kept working in the gap.

Get your H-1B I-9 trail audit-ready

Most H-1B I-9 errors are quiet — visible only when ICE asks for the file. Run your H-1B population through the i9 Intelligence Risk Calculator or book a free compliance call to see what's missing in your Section 2 Additional Information field, Supplement B history, and 240-day tracking.

3. H-1B portability (employee changes employers, comes to you from another H-1B sponsor)

This is the scenario where the attorney/HR gap is most expensive. Under H-1B portability — sometimes called "AC-21" after the American Competitiveness in the Twenty-First Century Act — an H-1B employee can begin working for a new employer as soon as the new employer files a Form I-129 on their behalf, provided the employee's authorized period of stay has not yet expired.

USCIS is explicit on what the new employer must do:

"An H-1B employee who is changing H-1B employers may begin working for the new employer as soon as the employer files a Form I-129 petition on behalf of the employee, however, the employer must do this before the employee's period of authorized stay expires. You must also complete a new Form I-9 for this newly hired employee. An H-1B employee's unexpired Form I-94 issued for employment with the previous employer, along with their foreign passport, qualifies as a List A document. You should write 'AC-21' and enter the date you submitted Form I-129 to USCIS in the Additional Information field in Section 2." — USCIS M-274, Section 7.5

The common employer error: treating a porting H-1B hire like a transfer with no new paperwork, or relying on the prior employer's I-9. Neither is acceptable. The new employer must complete a brand-new Form I-9, record the prior I-94 + foreign passport as List A, and write "AC-21" with the I-129 filing date in Section 2 Additional Information.

4. H-1B reverification at the end of the authorized period

When the Form I-94 (or the H-1B authorized period) is about to expire and a new I-94 has been issued — for example, after an extension approval — the employer must complete Supplement B. USCIS confirms that for H-1B reverification, "when an H-1B employee requires reverification of their continued H-1B employment authorization, they may choose to present their Form I-94, since only a List A or List C document is required for reverification."

The employee chooses what to present. The employer does not demand a specific document. Demanding the foreign passport when the employee only needs to present the I-94 is a document abuse claim under the Immigrant and Employee Rights Section (IER) framework, separate from any ICE substantive violation.

5. F-1 OPT to H-1B cap-gap

For STEM and non-STEM F-1 students transitioning to H-1B, the cap-gap automatically extends F-1 status and employment authorization through October 1 if a timely H-1B change of status petition is filed. The employer does not need to complete a new Form I-9 during the cap-gap if the same employee is staying with the same employer — but Section 2 Additional Information should reflect the cap-gap, and Supplement B is completed once the H-1B is approved and the new I-94 is issued.

Where the March 2026 ICE enforcement shift changes the math

Until March 2026, many H-1B-related I-9 notation errors — a missing "240-Day Ext." note, a forgotten "AC-21" entry, an unrecorded I-94 expiration — were treated as technical or procedural violations. Employers had a 10-business-day cure period after a Notice of Inspection to fix them before fines attached.

That changed when ICE issued its March 2026 I-9 Inspection Fact Sheet. ICE reclassified more than 10 categories of formerly technical violations as substantive — meaning no cure period applies. Several of these reclassifications directly affect H-1B paperwork:

• Missing or incorrect document expiration dates in Section 2 (the I-94 end date)
• Failure to complete Supplement B by the reverification deadline
• Missing notations on extensions of authorized stay

In practice: if your H-1B employee's 240-day extension period lapsed without a Supplement B, that is now a substantive paperwork violation on a Form I-9 inspection. Paperwork violations currently range from $288 to $2,861 per Form I-9 under the January 2025 Federal Register inflation adjustment. A 50-employee H-1B population with consistent notation gaps becomes a six-figure exposure on a single Notice of Inspection.

What "right" looks like — the H-1B I-9 operational checklist

Every H-1B employee in your population should have:

1. An original Form I-9 with Section 2 completed using the foreign passport and the H-1B-endorsed Form I-94 as List A (or another valid List A / List B + C combination the employee chose to present).
2. Section 2 Additional Information notations for every petition event: "240-Day Ext. + I-129 filing date" for in-place extensions, "AC-21 + I-129 filing date" for incoming porters.
3. A Supplement B entry for every reverification triggered by an I-94 expiration or extension approval, completed by the earlier of: USCIS decision date, the 240-day deadline, or the new I-94 expiration.
4. A copy of each new Form I-94 when reverifying (recommended for audit defense; employees can retrieve the I-94 from the CBP website).
5. A calendar that connects the immigration attorney's filing dates to HR's Supplement B obligations. Most organizations don't have this — the attorney files and HR finds out months later when the I-94 expires.

The last item is the one that's hardest to fix without a system. It's also the one that ICE inspections expose most often.

Why this gap exists — and what to do about it

"Immigration counsel and HR rarely share a system. Counsel ends at petition approval; HR begins at the I-9. The Form I-94 changes, the work authorization period shifts, and unless someone is actively tracking it, the Supplement B never gets done. That is the single most common H-1B finding in the audits we run," says Patricia Duarte, Director of Compliance at i9 Intelligence.

The fix isn't more legal spend. It's an I-9 process owner — internal or external — who tracks the petition calendar against the I-9 file, completes the Section 2 Additional Information notations on the day the I-129 goes out, and runs Supplement B on the day USCIS decides.

Quick reference — H-1B event → I-9 action

Stop guessing whether your H-1B I-9s are audit-ready

If your immigration attorney and your HR team don't share a Supplement B calendar, your H-1B I-9 file is almost certainly incomplete. i9 Intelligence runs H-1B-specific I-9 audits that map every petition event to the corresponding Section 2 notation and Supplement B entry. Learn about our audit services or book a demo to see how we close the gap between your counsel and your I-9s.

Need help

If you have a specific H-1B I-9 scenario or want to talk through your H-1B population, reach the i9 Intelligence team:

• Phone: (713) 668-6200 (Mon–Fri, 8 AM – 5 PM CT)
• Email: support@i-9intelligence.com
• Submit a ticket: i-9intelligence.com/submit-a-ticket