Activist investor Jana Partners disclosed in an SEC filing that it has acquired a 9% stake in grocery retailer Whole Foods, with an eye toward possibly pushing for a sale process. The move makes Jana the second-largest outside shareholder in Whole Foods, which saw its stock spike more than 9% on the news ― giving it a market cap of nearly $11 billion, and an enterprise value of around $12 billion. Key line from filing: Jana plans on speaking to company management and directors about "initiating a review of strategic alternatives particularly in light of the Issuer's apparent unwillingness to...