Express Scripts operates as a pharmacy benefit management company in the United States and Canada. Its PBM segment offers clinical solutions; and specialized pharmacy care, home delivery and specialty pharmacy, retail network pharmacy administration, benefit design consultation, drug utilization review, drug formulary management, public exchange, administration of group purchasing organization, and digital consumer health and drug information services. This segment also provides Medicare, Medicaid, and health insurance marketplace products; Express Scripts SafeGuardRx, a suite of solutions targeting the therapy classes that pose clinical challenges and budgetary threat to its clients; and Inside Rx, a program that provide affordable access to medication for uninsured and underinsured individuals. Its Other Business Operations segment distributes specialty pharmaceuticals and medical supplies, including injectable and infusible pharmaceuticals and medications to treat specialty and rare/orphan diseases. This segment also provides medical benefit management solutions for radiology, cardiology, musculoskeletal disorders, sleep disorders, post-acute care, genetic lab, specialty pharmacy, and medical oncology. The company serves patients, self-funded plans, health plans, regulated markets, workers’ compensation, physicians, and pharmacists. It operated 4 automated dispensing home delivery pharmacies; 1 non-automated dispensing home delivery pharmacy; 7 non-dispensing order processing centers; 5 patient contact centers; 9 specialty home delivery pharmacies; and 34 specialty branch pharmacies as of December 31, 2017. Aristotle Holding that began operation in 1986 became Express Scripts Holding Company in April 2012, with its headquarters in Saint Louis in Missouri. Express Scripts operates as a subsidiary of Cigna as of December 20, 2018.