Training records, permitted project descriptions, internal qualification documents and similar evidence can accurately explain the knowledge involved. Ask the employer to identify what can be shared openly and what needs special handling.
Choose records that answer the actual question
The reviewer needs to understand the process and the person's experience with it, not an unexplained volume of sensitive files. Ask which examples establish the key facts, and coordinate with the employer on how confidential details will be handled. Removing too much context can leave the claim unsupported even if the underlying facts are genuine.
Build the file from contemporaneous company material, not a narrative written after the transfer is proposed. Date the technical artifacts, link the employee to them, and explain any confidentiality limits without withholding the core proof. Hypothetical example: a Québec firm producing optical-sorting equipment says its calibration specialist is essential to a U.S.
installation. The best evidence is the dated calibration manual, her training logs, and a staffing record showing how few workers can perform the task. A supervisor’s conclusory letter can guide the reader, but it cannot replace those underlying records from the period.
They should be retained.