Described by Atlanta magazine as a "serial" entrepreneur,[9] he has founded multiple health care companies, including cardiac monitoring business Quality Diagnostic Services (QDS), medical website WebMD,[10] and Atlanta-based Sharecare,[3] for which he is chairman and chief executive officer (CEO).

[5][16][17] In 2001, he formed The Convex Group,[18] a vulture fund, for which he also was chairman and CEO.

[26] In 2003, Arnold started LidRock, which produced promotional miniature CDs attached to the lids of fountain drinks.

[28] Arnold purchased 19 patents from various companies in order to produce the LidRock concept.

[18][29][30] The CDs were typically sold at fast-food restaurants and movie theaters,[31][30][27] and generally were used to promote new video games or music from singers such as Britney Spears.