8 CFR 214.2(l)(1)(ii)(D) states
SPECIALIZED KNOWLEDGE means special knowledge possessed by an individual of the petitioning organization’s product, service, research, equipment, techniques, management, or other interests and its application in international markets, or an advanced level of knowledge or expertise in the organization’s processes and procedures.
Therefore, it is required that we submit evidence to establish that the beneficiary meets the criteria stated above in order to qualify as an L-1B non-immigrant with Specialized Knowledge. Further the USCIS requires that the knowledge be special such that it is distinguishable from general knowledge in the field or industry. If the Specialized Knowledge is applied “hands-on,” the USCIS requirement has often been for a significant, documented training program. An alternative may be developed, but typically requires additional involvement by your staff and our office. If the Specialized Knowledge is applied more conceptually at a professional level the USCIS has often been satisfied with a summary of the project(s) that the individual has been engaged and technical or semi-technical brochures.
For this we should prepare a letter signed by an individual authorized by the prospective employer describing the alien’s employment addressing this requirement. Further for the general L regulations we would show that the alien was employed by a properly related entity for one continuous year abroad within the three years immediately preceding the filing of this petition, or if the alien is already in the U.S., immediately preceding his/her entry as a non-immigrant, and describing the intended employment in the U.S. The statement would additionally include information concerning the dates of employments, job titles, specific job duties, types of employees supervised, if any, level of authority, and title and level of authority of the alien’s immediate supervisor.