Share registers or equivalent ownership records for both entities, shareholder agreements, incorporation and annual filings, and evidence that each company is actively doing business. Payroll records for the transferee's last three years belong in the same file.
Two stacks: who owns it, and is it running
Keep the file in two clearly separated parts, because they answer two different questions. The ownership stack shows the qualifying relationship: the registers, the agreements, the corporate filings that each jurisdiction requires, and any trust or holding-company documents that sit between the individuals and the operating companies. The activity stack shows both entities are doing business: leases, customer contracts, invoices, tax filings, staff lists and premises evidence for each side. Ask the accountant for both stacks at the same time, since the accountant usually holds them and can flag discrepancies that nobody else will notice. Finally, pull the transferee's own payroll and employment records covering three full years back, because the qualifying-year requirement is proved from those and reconstructing them later is unpleasant.
Hypothetical example: Leena, a museum-services executive, has organization charts but no record proving who can appoint directors. She should obtain the shareholder agreement, share register, appointment resolutions and any voting trust before relying on the chart. Those records establish ownership and control; payroll and contemporaneous duty evidence must separately prove one continuous qualifying year abroad. Her U.S. file also needs a role map showing primarily managerial or executive authority and the staff or function beneath it. The document chronology should include prior L admissions because L-1A has a seven-year maximum. A newly prepared summary cannot replace the governing corporate instruments when they answer who actually controls each entity.