Through ordinary business records on each side: tax filings, financial statements, payroll registers, customer contracts, premises documents and evidence of continuing commercial activity.
Trading, not merely incorporated
An established Canadian contractor satisfies this easily and the records already exist. The counterpart abroad is where the question actually lands. If it has been operating, gather signed customer agreements, a premises document, equipment in service, employees on a payroll, tax registrations and any trade licensing the work requires. If it exists only on paper, the situation is a newly established operation, which is assessed differently and needs evidence of secured premises and the financial capacity to carry the transferred role through a first year. Determining which of those two situations applies is a prerequisite for knowing what to assemble, so it belongs near the front of the sequence rather than in the middle of drafting.
Ask for records in the order that proves the threshold facts: formation documents and ownership evidence, dated payroll records, then operations evidence and role materials. A single corporate chart is helpful but does not replace share certificates, registers, or agreements. A payroll summary should be checked against underlying payslips or tax records where dates matter. The decision is whether each fact has a primary record, not whether the packet looks substantial. Hypothetical example: an emergency-lighting distributor discovers its manager moved between affiliates midyear, so it collects the transfer documentation and pay records before describing the employment period as continuous.