With trading now closed in the U.S., Apple has ended the day with a lead on Exxon Mobil, becoming the most valuable publicly traded company by market capitalization.

The Cupertino, Calif.-based technology company passed Exxon yesterday during trading for the first time, only to end up the same way it began the day, below Exxon. According to Yahoo Finance Apple currently sits at $337.17 billion, compared to Exxon's $330.77 billion.

Market capitalization is defined as the value of shares times the number of shares outstanding. Exxon surpassed General Electric, based on that metric, in 2005.

The benchmark comes 14 years after Apple was bailed out by Microsoft in a $150 million investment and partnership deal that had the two companies doing business together at a time when Apple's future was unclear. In its rise to the No. 1 market cap spot, it passed Microsoft in that same metric early last year.

Despite the title win for Apple in trading today, its stock closed down 2.76 percent at $363.39 per share.