CVS Health announced on Nov. 4 that it plans to split into two independent, publicly traded companies, reversing two decades of deals that combined pharmacies, insurance and medical services under one roof.

One company, keeping the CVS Health name for now, will hold the insurer Aetna, the pharmacy benefit manager CVS Caremark, CVS Specialty, Oak Street Health and Signify Health. It will be led by CEO David Joyner.

The other, called CVS Pharmacy, will run about 9,000 drugstores, the mail-order pharmacy and MinuteClinic. It will be led by Prem Shah, now a group president at the company.

The split is expected to be finished in the first half of 2028. Until then, CVS says it will operate as it does today, and current shareholders will own shares in both companies.

The move comes as lawmakers and regulators look more closely at companies that combine insurance, pharmacy benefits and drugstores.