Corporate documents proving the qualifying relationship, payroll records covering the qualifying year, and a detailed evidentiary record of the knowledge itself: design and technical documentation, internal training materials, deployment history and a duties description tying all of it to the United States assignment.
Three files: the relationship, the year, and the knowledge
The first two are administrative and rarely contentious once someone is assigned to gather them. The third is where cases are won. Useful items include technical specifications the beneficiary authored, internal training curricula she delivered or received, records of prior implementations she led, and a comparison of her knowledge against what the labour market offers. Letters from senior technical staff describing specific problems only she has solved carry weight when they are concrete. Equally important is a description of the United States role that requires the knowledge: an assignment described as general information technology support undercuts a claim of specialized knowledge no matter how strong the background. The role and the knowledge have to be the same shape.
Hypothetical example: a robotic-milking systems technician has confidential manuals and project reports. The review should decide how to demonstrate knowledge without disclosing unnecessary material, using redacted exhibits, technical declarations, employment proof, and matching duties. Build an exhibit list naming what each item proves and where its date appears. Obtain a replacement or explanation while the source is available. The common error is that dense attachments without a guide do not establish the required connection. Reconcile names, dates, amounts, and role descriptions before reliance.
Use a concise exhibit index that connects every technical record to the proposed duties.