Locating your LinkedIn Company ID
If you require your Company ID, this article describes how to locate it:
https://www.linkedin.com/help/linkedin/answer/a415420/associate-your-linkedin-company-id-with-the-linkedin-job-board-faqs
Understanding LinkedIn URNs
URNs are used to represent foreign associations to an entity (persons, organizations, and so on) in an API. A URN is a string-based identifier with the format: urn:{namespace}:{entityType}:{id}
For example:
urn:li:person:123urn:li:organization:456urn:li:sponsoredAccount:789