Microsoft has begun to narrow down its list of potential replacements for outgoing CEO Steve Ballmer, reports Reuters.

The list is impressive, including Nokia CEO Stephen Elop, Ford Motor Co chief Alan Mulally, former Skype CEO Tony Bates, and Satya Nadella, who heads cloud and enterprise at Microsoft.

Elop and Mulally have been tipped before for the position, so it's interesting to hear the search committee within Microsoft firm up the last few candidates. According to Reuters, the search could still take a few months - after all the latest they have is until next August when Ballmer plans to retire from the company for good.

But Ford people has once again denied Mulally plans to leave the company. It said: "There is no change from what we announced last November. Alan remains fully focused on continuing to make progress on our One Ford plan. We do not engage in speculation." Nonetheless, Mulally has stayed on the list from Reuters.

Let's take a look at the candidates. Bates and Nadella already have experience running key divisions within Microsoft, so it can be feasible why the search committee is looking into them as replacement. Mulally is known for his forward thinking and potential to turn Microsoft around like he did with Ford, and Elop has worked extensively over the years with Microsoft in the handset game.

Even with a big list of names, investors are pressuring the search committee to look into other options outside the realm of inner Microsoft to turn things around, according to Reuters.

Though he will be leaving his CEO position, Ballmer still has the opportunity to stay on Microsoft's board if elected to do so, along with Microsoft founder Bill Gates. Some investors want Gates out from the chairman position he holds at Microsoft.

It's going to be an interesting few months for Microsoft's leadership.