CVS Health offers a diverse set of healthcare services. Its roots are in its retail pharmacy operations, where it operates over 9,000 stores primarily in the U.S. CVS is also the largest pharmacy benefit manager (acquired through Caremark), processing over 2 billion adjusted claims annually. It also operates a top-tier health insurer (acquired through Aetna) where it serves about 26 million medical members. The company's recent acquisition of Oak Street adds primary care services to the mix, which could have significant synergies with all its existing business lines.