FORTUNE -- Two years ago Apple (AAPL) made headlines when its market capitalization (share price times number of shares outstanding) overtook Exxon Mobil's (XOM) for the first time.
In January, with Apple's share price in a tailspin, the big news everywhere from the Wall Street Journal to the Huffington Post was that Exxon was once again the market cap king -- the world's most valuable company.
When Apple retook the lead the next day, almost no one noticed. Perhaps that news didn't fit the Apple-is-doomed narrative.
Now, having lost and regained the lead several times since, Apple is once again pulling away from the oil giant. By midday Monday, with Apple at $434.4 billion and Exxon at $404.8, the gap between the two companies' valuations had swelled to roughly one and a quarter Dells (DELL).
Exxon Mobil finished 2011 where it started: As the world's most valuable company
It was nip and tuck for more than three months, from that day in early August, when Apple (AAPL) first overtook Exxon Mobil (XOM), to mid November, when Exxon finally pulled away.
At one point in late September, Apple's market cap (share price times number of outstanding shares) was nearly $36 billion more than Exxon's.
But though Apple's shares ended the MORE
Philip Elmer-DeWitt - Jan 2, 2012 11:58 AM ET
Apple (AAPL) got clobbered Thursday, losing $10.32 (2.5%) to close at $401.82. But it got clobbered less than the rest of the market. Exxon Mobil (XOM), in particular, fell 3.79%.
Bottom line: Apple, whose market capitalization trailed Exxon's by $50 billion three months ago, and which first overtook Exxon six weeks later, is now the world's most valuable public company by $35.87 billion.
Philip Elmer-DeWitt - Sep 22, 2011 5:37 PM ET
When the rest of the market is tanking, the company's shares offer a relatively safe haven
On Monday, when the Dow opened down $250, Apple (AAPL) rose $11.13 (2.78%) to close at a new record $411.63. On Tuesday, Apple opened at $415.35 and hit $422.86 shortly after noon.
UPDATE: Apple closed Tuesday nearly where it started, at $413.45, up $1.82 (.44%) for the day.
To put Monday's close in perspective:
Apple shares were up MORE
Philip Elmer-DeWitt - Sep 20, 2011 7:33 AM ET
When the market closed, it was once more the world's most valuable public company
When analysts warned that the greatest risk to Apple's (AAPL) share price was Steve Jobs, they assumed that when he stepped down the stock would fall.
So much for that theory.
If the market action Thursday was ambiguous (the stock fell a bit, but less than the major indices), the message Friday was not. Apple rose $9.86 (2.64%) to close MORE
Philip Elmer-DeWitt - Aug 26, 2011 7:22 PM ET
The closing bell rang Wednesday with Apple's market cap, for the first time, at No. 1
Apple (AAPL), for now at least, is the world's most valued company by market capitalization (determined by multiplying a company's stock price times number of shares outstanding). Here's how it happened:
It caught up to Google (GOOG) in mid-2009
It overtook Walmart (WMT) in March 2010
It passed Microsoft (MSFT) in May 2010
It caught up to Exxon Mobile MORE
The computer maker is once again the world's most valuable company
As the Dow Jones industrial average plunged another 500-plus points Wednesday, Exxon Mobil (XOM) plunged more than Apple (AAPL) and once again gave up its long-held spot as the No. 1 public company in the world in terms of market capitalization.
When the closing bell rang, Apple closed on top for the first time. The tale of the tape looked like MORE
Philip Elmer-DeWitt - Aug 10, 2011 11:55 AM ET
The company's market cap vied with Exxon Mobil's in see-saw trading Tuesday
The lead changed hands several times Tuesday as Exxon Mobil (XOM) recovered from early losses and Apple's (AAPL) gains leveled off. By 3:00 p.m, Apple's market capitalization (share price times number of shares outstanding) was more than $5 billion larger than Exxon's, according to Google Finance. As the closing bell approached, however, Exxon surged faster than Apple and retook the MORE
Philip Elmer-DeWitt - Aug 9, 2011 2:01 PM ET
With its market cap at $213.9 billion, only two U.S. companies are bigger than Apple
Here's one way to measure Apple's (AAPL) progress in March, a month in which its stock price set 11 all-time highs.
On March 9, a few days after the company announced the iPad's ship date, Apple's market capitalization (share price times shares outstanding) was $198.5 billion, making it one of the five most valuable U.S. companies, right MORE
Philip Elmer-DeWitt - Mar 31, 2010 6:34 AM ET
Shares surge on iPad pre-orders, making Apple America's third most valuable company
UPDATE: That was short-lived. By March 15, Apple's market cap had fallen below Wal-Mart's once again.
Ninety minutes after Apple (AAPL) opened its online store for iPad pre-orders Friday morning, a burst of trading -- roughly 2 million shares in 30 minutes -- pushed its stock price to $227.73 and its market cap to $206.5 billion.
That, and a dip in MORE
Philip Elmer-DeWitt - Mar 12, 2010 10:43 AM ET