The actual offsite arrangement must be reviewed under the control and labour-for-hire restrictions, alongside all other requirements.
Explain who directs the work
Do not decide from the address alone. Identify the employer’s role, the customer’s authority and the real service being performed.
The petition should explain why the claimed knowledge is particular to the company rather than merely a general engineering skill; there is no separate requirement to prove that workers are unavailable in the US labour market. Explain the particular internal system, technique, product architecture, service model, or process at issue; state how the employee acquired it; and show what U.S. work depends on it. L-1B assessment should explain that knowledge under the applicable standard rather than assume that public disclosure automatically defeats the claim or that confidential language automatically proves it. Start with the actual process: versions of internal manuals, training modules, controlled procedures, project histories, and access records can explain why the knowledge is special or advanced. Command of a proprietary control platform's fault-tolerance logic, acquired inside the company, belongs to the employer and is what the category is for. The practical choice is whether the assignment uses the particular organizational knowledge or instead describes routine production, customer support or skills available in the general labour market.