Last year, Apple (Nasdaq: AAPL) briefly enjoyed, by market cap, the title of "largest company in the world."

During the selloff that kicked off August, the Mac maker surpassed Exxon Mobil (NYSE: XOM) and became the new king of the hill. After enjoying its time in the sun, a few short months later Apple graciously relinquished the crown back to the oil baron, thanking it for the loaner.

Today, Apple hit a new market-cap milestone as it broke into uncharted territory. As of this writing, Apple's intraday high has been $431.37, and when you multiply that by the 932 million shares outstanding, you'll notice that its market cap reached as high as $402 billion, breaking $400 billion for the first time ever.

Apple Market Cap Chart by YCharts.

Note that the chart above represents market caps based on the previous day's close, as opposed to the intraday figure calculated above for Apple. Exxon still reigns as top dog with roughly a $422 billion market cap, but it's safe to say that Apple is still the largest tech company in the world by market cap. Cupertino topped Microsoft's (Nasdaq: MSFT) market cap back in 2010 and has never looked back. The Redmond giant's market cap currently stands near $237 billion.

Looking at revenue on a trailing-12-month basis, Apple has also recently squeezed out a lead over fellow tech giant IBM (NYSE: IBM), while still trying to catch up with Hewlett-Packard's (NYSE: HPQ) top line.

Apple Revenues TTM Chart by YCharts.

When it comes to competing with HP, Apple may be about to swoop in and steal a different title from the embattled PC maker. If you assume that the iPad counts as a PC, which is a distinction debatable from both perspectives, then Apple may be about to claim the name, by shipments, of top PC maker in the world.

With Apple set to report earnings on Tuesday, with hints of a blowout, we'll see how Mac and iPad shipments turn out and whether or not Apple can take the lead.

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