The video of Winfrey's speech, which explored issues of race, gender and other social and political hot buttons, went viral. Despite a backstage denial by Winfrey, her speech and subsequent reports fueled speculation that she may be considering a presidential run in 2020.
Oprah has made Weight Watchers an investor magnet since buying a 10 percent stake in the company over two years ago. Her $43 million initial investment of 6.4 million shares in October 2015 more than doubled Weight Watchers stock that same day.
Since then, Winfrey's investment has accumulated value close to $300 million, and the overall stock has shot up more than 350 percent year-to-date.