When a user clicks on the Follow Company button, they will automatically begin following the company.
http://developer.linkedin.com/plugins
Widgets
Get access to data on 101,486 websites that are LinkedIn Follow Company Plugin Customers. We know of 44,078 live websites using LinkedIn Follow Company Plugin and an additional 57,408 sites that used LinkedIn Follow Company Plugin historically and 21,827 websites in the United States.
Get a list of 101,486 websites using LinkedIn Follow Company Plugin which includes location information, hosting data, contact details, 44,078 currently live websites and 57,408 sites that used this technology previously and 21,827 websites in the United States currently using LinkedIn Follow Company Plugin.