Another major milestone for Apple Inc. (NASDAQ:AAPL) today. The company hit a new 52-week high of $575.14 today, suggesting that it could be in the process of making a major comeback. Of course we’re still a long ways from last year’s high of $705 a share, but still, this is major progress.

Apple Inc. AAPL

Multiple factors boosting Apple shares

Right now Apple has several things going for it. The company has reported great sales numbers for the new iPhones since they launched, and now there are other data points suggesting that the new iPads are selling extremely well too. History shows that investors appear to like big sales numbers more than anything else when it comes to Apple.

However, in this case we also have the interference of activist investor Carl Icahn. He filed a precatory proposal to call for a vote on an increased share buyback plan. He’s clearly handling Apple Inc. (NASDAQ:AAPL) management with much more respect than he does management of other companies. He has dialed down his demands a bit—from $150 billion down to $50 billion, which Apple may see as more doable.

Will Apple follow through with its share price higher?

Writing on The Motley Fool, Daniel Sparks considers whether it makes sense for Apple to follow through with Icahn’s push as shares go higher and higher. When Icahn started pushing for that buyback, shares were meaningfully lower than they are now. In fact, shares were under $500 at that point, and now they’re approaching $600. But even when the stock hit $565, he was still pushing, which suggests just how much he thinks Apple Inc. (NASDAQ:AAPL) shares are worth.

Of course buying back shares at current levels will not provide the same benefits it would have at $500 or less. However, Icahn is apparently looking at this in terms of the amount of cash Apple Inc. (NASDAQ:AAPL) has on hand. It’s around $148.6 billion, and it will continue to generate cash. Icahn tends to back off the net cash. At this method, Apple’s multiple is 11 times earnings.

What is Apple really worth?

Multiple analysts continue to rate Apple Inc. (NASDAQ:AAPL) as a buy, even at current levels, so clearly others agree with him that the shares should be worth more. But is a share buyback the answer to boosting the share price? Moody’s thinks that whatever the company does, it should avoid taking on more debt.