Steven Bartlett founded the British marketing company Social Chain before joining Dragons' Den.
Social Chain grew from a social-media project into an international marketing business. Bartlett co-founded the company with Dominic McGregor, and its work focused on digital communities, social platforms, and brand campaigns.
Bartlett's experience building a digitally native company helped define his profile when he joined Dragons' Den. His route differed from that of investors whose wealth came primarily from retail, property, manufacturing, or traditional finance.
Social Chain is sometimes confused with Bartlett's podcast and publishing work because all three are strongly associated with his public identity. The company, however, was his major early business venture and the specific answer here.