When a user clicks on the Follow Company button, they will automatically begin following the company.
http://developer.linkedin.com/plugins
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Get access to data on 104,611 websites that are LinkedIn Follow Company Plugin Customers. We know of 25,427 live websites using LinkedIn Follow Company Plugin and an additional 79,184 sites that used LinkedIn Follow Company Plugin historically and 12,505 websites in the United States.
Get a list of 104,611 websites using LinkedIn Follow Company Plugin which includes location information, hosting data, contact details, 58,106 currently live websites which includes 32,679 domains that redirect to sites in the list. 79,184 sites that used this technology previously and 12,505 websites in the United States currently using LinkedIn Follow Company Plugin.