I want to use the Linkedin API to get details of jobs posted by any company. This data seems to be public, so do I need to integrate Oauth?
The data is not quite public. You need an API key and you need oAuth to make API calls. Probably you dont need it if you just want the public profiles. Read the docs (RTFM).
http://developer.linkedin.com/rest
http://developer.linkedin.com/documents/job-search-api