Uber wants Facebook COO Sheryl Sandberg to replace Travis Kalanick as its CEO, a source close to board member Arianna Huffington tells Inc.

Kalanick, who helped launch Uber in 2009, resigned as chief executive this week after shareholders staged a revolt. Five investors--Benchmark Capital, First Round Capital, Fidelity Investments, Lowercase Capital, and Menlo Ventures--had sent Kalanick a letter on Tuesday demanding that he step down amid a tumultuous period for the ride-hailing giant.

Sandberg will be staying on at Facebook, however, a source close to her tells Inc.

The decision makes sense, given that the billionaire business mogul has plenty on her plate. Sandberg is reportedly mulling a run for U.S. president, and taking the top job at the company would come with a great deal of reputational risk, analysts say. It's worth pointing out that Kalanick continues to hold the majority of voting shares, and therefore will have some say in the future of the business regardless.

Huffington declined to comment when contacted by Inc. Uber did not immediately respond to Inc.'s request for comment.

Sandberg isn't the only executive who sources say could lead Uber moving forward. Some suggest that other candidates could include Meg Whitman, president and CEO of Hewlett Packard Enterprise; Jeff Immelt, the former CEO of General Electric; Mark Fields, formerly the CEO of Ford; and Adam Bain, Twitter's former COO.

Bradley Tusk, the founder of Tusk Holdings and an Uber adviser, also points to the chief executive of Amazon. "The one name that comes to mind of someone who can make the most of Uber and run it well is Jeff Bezos," Tusk tells Inc. "Obviously, that would come in the form of an acquisition." Just last week, the e-commerce giant announced that it would acquire Whole Foods for $13.7 billion, in a move that has major implications for the future of retail.

A big shift

Still, a new chief will be a dramatic change for the eight-year-old startup--most recently valued at $70 billion. It has long been seen as an extension of its caustic founder. Kalanick's leadership style often came at the expense of corporate ethics; early mottoes at the startup included "always be hustlin'" and "stepping on toes." Once, Kalanick reportedly signed an email, announcing that employees working on the same teams at Uber would not be permitted to have sex with one another on a company trip, with #FML.

Yet Kalanick's position at Uber became indefensible for shareholders amid a number of crises this year. In February, Alphabet's self-driving car unit, Waymo, filed a lawsuit against Uber alleging trade secret theft. Meanwhile, a former Uber engineer published a blog post alleging sexual harassment and gender discrimination during her tenure at the company. This prompted Uber to hire former attorney general Eric Holder, through his law firm Covington & Burling, to lead an investigation into the workplace culture. (The entire 13-page report and its recommendations, which included minimizing Kalanick's role at the company, can be found here.) In recent weeks, the company has fired more than 20 people, in response to more than 200 complaints.

Last week, Kalanick announced that he would be taking a temporary leave of absence from the company, in part to mourn the loss of his mother, who died in a boating accident last month.

"I love Uber more than anything in the world and at this difficult moment in my personal life I have accepted the investors' request to step aside so that Uber can get back to building rather than be distracted by another fight," Kalanick told The New York Times in a prepared statement.