Clover’s investors are hoping that the company can upend a segment of the huge $220 billion health insurance market . But it is a huge challenge because insurance giants like United Healthcare already dominate and have huge resources to fend off small rivals. Clover says that its algorithms and software identify the patients most at-risk of hospitalization or costly treatments. It then may send nurse practitioners to visit those patients’ homes and coordinate necessary tests that may be missing in their medical files. The company also analyzes lab data to identify patients who are in danger of serious illness like diabetes. The goal is to counsel them before they require costly treatments.

http://fortune.com/2015/12/16/sequoia-capital-clover-health/