Fresh off its success with Whole Foods, Jana takes new stakes in Pandora, Sunoco, others

  • Parts of a letter to clients obtained by CNBC reveal new positions by the activist investor.
  • Jana swooped in on Pandora Media after it failed to sell itself.
  • Its Sunoco stake is a "special situation" after it sold gas-station assets to 7-Eleven.
Barry Rosenstein, managing partner and co-portfolio manager of JANA Partners LLC.
Adam Jeffery | CNBC
Barry Rosenstein, managing partner and co-portfolio manager of JANA Partners LLC.

Fresh off his success with Whole Foods Market, Jana Partners' Barry Rosenstein has snapped up shares of Pandora Media, Sunoco, Hewlett Packard Enterprise and a couple of other companies, according to parts of an investor letter obtained by CNBC.

At Pandora, the activist investor said in the letter, "we see a great product with a large base of users and an enormous opportunity to grow advertising revenues and to run the business more efficiently."

Jana added that the investment followed the failure of Pandora to sell itself, instead raising a $480 million investment from Sirius XM, a 16 percent stake.

Last week, Jana said it is cashing out of its 26 million shares of Whole Foods, which agreed last month to be acquired by The Whole Foods stake resulted in about $300 million of profit. Jana first reported its ownership of the grocery chain in April, nudging the company to accelerate its turnaround plan or find a buyer.

The stake in Sunoco is a special situation, Jana said. The company is selling its gas-station assets for cash to Seven & i Holdings Co., the owner of the 7-Eleven store brand. This deal will reduce the debt load at the company "to a manageable level," according to the letter.

It is Jana's second time taking a stake in Hewlett Packard Enterprise. HP Enterprise has missed earnings targets in two recent quarters in its core server business, trading at 7 times earnings when hardware rivals Cisco Systems, Juniper Networks and NetAPP trade an average of 12 times earnings, an excerpt of the letter said.

Jana also took activist stakes in natural gas producer EQT, which it says should separate its pipeline businesses rather than buy Rice Energy, and Zimmer Biomet, a medical-device maker.

Scott Wapner contributed reporting.

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