Payroll registers or pay statements covering every month, the employment or secondment agreement, assignment letters, leave records, and corporate documents showing the ownership relationship between the foreign employer and the U.S. entity. Together they should account for the period without unexplained gaps.
Account for every month, including the awkward ones
The strongest version of this evidence is a simple schedule listing each month with the employing entity, the capacity and the supporting document, so that a reader can see the year is unbroken without reconstructing it themselves. Gaps should be explained rather than omitted: parental leave, a plant shutdown, a medical absence and a period of unpaid leave have different consequences and are better addressed directly. Where an assignment was documented only by email, that correspondence is still evidence and should be preserved.
Ask the group's human-resources function for records early, since retrieving payroll data from a foreign entity's system can take weeks. A licensed U.S. immigration attorney should decide what the file needs.
Hypothetical example: Sigrid works on water-treatment membrane specifications shared within a global group. Her document pass should assemble payroll records, secondment terms, foreign job descriptions, the ownership chain, product manuals with access controls and evidence of the U.S. need.
Corporate filings establish the required corporate link between the overseas company and American entity; dated training records settle whether her expertise belongs to the organization. Request material directly from the teams that created it, rather than asking them to recreate history in a support letter. A common failure is filing generic brochures that show the product but not the worker’s advanced familiarity with it.
Explain any employment gap instead of hoping it is overlooked.