Activist investor Starboard Value LP has taken a stake in CVS Health Corp. and held talks with the drugstore-and-insurance giant's management, according to people familiar with the matter.
The stake appears to be relatively small and the people said the talks, held recently, are amicable. How much Starboard currently owns and what it has discussed with the company couldn't be learned. But Starboard is one of the top activist-investment firms and its presence in a stock usually causes a company to sit up and take notice.
CVS shares have been on a roller-coaster ride since the company acquired health insurer Aetna Inc. for nearly $70 billion almost a year ago. The deal married CVS's sprawling drugstore network and pharmacy-benefit manager with one of the nation's largest health insurers.
The stock fell sharply after the Woonsocket, R.I., company in February issued a downbeat earnings projection for the year due to challenges in its pharmacy-benefits and long-term-care businesses. The shares went on to rebound sharply as the company reported a string of unexpectedly strong financial results, and research analysts have taken a more favorable view.
Shares of CVS rival Walgreens Boots Alliance Inc. have slumped about 25% in the past year as revenue from prescription-drug sales slows and competition from online retailers grows. Walgreens shares have been buoyed in recent weeks by reports of private-equity interest. No such deal appears to be imminent, people familiar with the matter say.
CVS stock, at around $76, is little changed in the past year compared with a big gain in the S&P 500 index. CVS's market capitalization currently stands at about $100 billion.
Some investors have privately expressed frustration over rising costs from CVS's Omnicare drug-distribution business, the lack of a clear plan for a successor to Chief Executive Larry Merlo and the large size of its 16-member board -- a legacy of the Aetna deal.
Bankers and lawyers who advise companies facing threats from activists say the investors are increasingly taking stakes in large targets and engaging with management instead of immediately going public with their demands. More often, the investors and their targets are finding common ground. Sometimes the campaigns never surface publicly.
Starboard has a record of ushering in change at companies ranging from eBay Inc. to Darden Restaurants Inc. Earlier this year, it urged eBay to exit businesses unrelated to its core marketplace after taking a stake in the San Jose, Calif., company. On Monday, eBay agreed to sell its StubHub ticketing business for more than $4 billion.
Starboard didn't report a stake in CVS in its latest quarterly filing with the Securities and Exchange Commission. Those filings are delayed -- the latest revealed the New York hedge fund's holdings as of Sept. 30 -- and some information may be omitted as investors can receive confidential treatment if they are in the process of building a position.
--Sharon Terlep contributed to this article.
Write to Corrie Driebusch at corrie.driebusch@wsj.com