IN THIS GUIDE · Keep control of an L-1B specialist who will spend the whole assignment on a client's mine site
Start with the L-1B eligibility and application overview
The specialized-knowledge and transfer conditions
L-1B requires one continuous year of employment abroad with a qualifying related entity within the preceding three years, a qualifying relationship between the entities, and both doing business. The knowledge must be special knowledge of the company's product, service, research, equipment or techniques and their application in international markets, or an advanced level of knowledge of its processes and procedures. General skill in the field, however expert, is not enough. L-1B is capped at five years, and prior L-1 time counts toward it. L-2 spouses are employment-authorized incident to status. The qualifying year must fall within the three years preceding filing, so payroll and travel records should be read together. Prior L-1 time also needs to be counted before a multi-year assignment is promised.
The offsite-placement rule
Where an L-1B worker will be stationed primarily at the worksite of an unaffiliated company, the petition must show two things: that the worker will not be principally controlled and supervised by that unaffiliated company, and that the placement is in connection with the provision of a product or service for which specialized knowledge specific to the petitioner is necessary. A monitoring contract in which the client's site manager assigns the technologist's daily tasks, sets his hours and reviews his work is a labour-for-hire arrangement and fails, regardless of how proprietary the protocol is. The service description should say what result the affiliate delivers and why this specialist is needed to deliver it. A site-access requirement does not transfer managerial control to the client.
Draft the client contract with the rule in mind
The affiliate's contract with the mine should describe a deliverable, not a body. It should state that the affiliate is providing a monitoring service under its own protocol, that the affiliate's project manager directs the technologist's work and evaluates it, and that the client's role is site access and safety orientation. Reporting lines should run to the affiliate, with a named supervisor who visits the site or reviews data on a set cadence. Keep his equipment, laptop and data systems the affiliate's own. Where the client insists on controlling the schedule, negotiate that clause before filing rather than hoping the officer does not read it. If the contract changes after filing, compare each amended control clause with the petition. A seemingly routine change to approvals, hours or replacement rights can alter the analysis.
Proving the knowledge is the company's, not the profession's
Every hydrogeologist can sample a well. The evidence must show what is different about the company's protocol: internal method documents with revision history, training records showing he was taught it and later taught others, examples of client audits or regulator submissions that relied on it, and a comparison explaining how it departs from standard published methods. Add a statement of how long it would take to train a U.S. hire to the same level, and why that is not practical for this contract. Avoid inflating his contribution; if he refined the field procedure but did not write the validation algorithm, say so. Use a focused technical exhibit with a glossary and a redaction key. It lets a reviewer understand the specialized process while protecting material that is genuinely confidential.
Sources reviewed 2026-09-07. This guide covers a preparation focus; it is not an individual eligibility assessment.