Neuberger Berman urges board to review options, including sale or joint venture Another big investor is calling on Whole Foods Market Inc. to explore a sale. Mutual-fund manager Neuberger Berman, which owns a 2.7% stake in the organic grocery chain, sent a letter to the company's board this week urging it to "immediately engage advisors" to review options including a sale or joint venture. The letter, which Neuberger provided to The Wall Street Journal, comes a few weeks after activist investor Jana Partners LLC disclosed a nearly 9% stake in Whole Foods and called for a similar review. Neuberger has been in talks with Whole Foods since last year but hasn't previously gone public with its suggestions for the chain, which is adopting strategies used by traditional grocer to boost flagging sales.