Shares of Herbalife Nutrition Ltd. /zigman2/quotes/201199224/composite HLF 0.00% fell 2.1% in morning trading Wednesday, after billionaire activist investor Carl Icahn said his Icahn Enterprises L.P. /zigman2/quotes/208212352/composite IEP -1.21% sold 14.7 million of the nutritional supplements company's shares, which reduced its stake in the company by about 42%. Icahn said the stock sale was part of Herbalife's self-tender offer, in which it accepts to buy back up to $750 million worth of its shares at $48.75 each. At that price, the 14.7 million shares Icahn sold would be valued at $716.6 million. Icahn Enterprises' stock rose 1.3% in morning trading. Icahn remains Herbalife's largest shareholder with about 20.5 million shares, or 15.5% of the shares outstanding. Herbalife's stock has dropped 8.6% amid a four-day losing streak, since it closed at a 14-month high of $52.63 on Aug. 6. The stock has gained 0.8% year to date, while the S&P 500 /zigman2/quotes/210599714/realtime SPX -0.72% has tacked on 4.3%.