Apple became the most valuable public company of all time on Monday when the combined value of its shares exceeded a previous record set by Microsoft.
Apple traded at $US664.74 ($AU635.88), giving it a market value of $623.14 billion. The value exceeded a previous record set by Microsoft of $620.58 billion in 1999 at the height of the tech bubble, according to data provided by S&P Dow Jones Indices.
The iPhone maker has been the biggest public company in the world since overtaking Exxon Mobil to reach the number one spot last year, but Monday's move means that it has now entered the record books as the biggest company ever.
At Monday's close of trade, Apple shares need to settle at $657.50 for the record to be set on a closing basis as well, according to S&P Dow Jones indices. The shares were trading 2 percent higher to $661.15 at around 1.19 p.m. EDT (5.19pm GMT).
Apple shares have rallied as investors anticipate the release of the iPhone 5 and possibly an iPad mini in September as well as more details about the company's plans for an Apple TV, according to analysts at Bernstein Research.
"Everyone loves a winner, if you play the quick trade be careful," said Howard Silverblatt, senior index analyst at S&P Dow Jones Indices in emailed comments.
"If you are an investor check the fundaments and business plans, and avoid the hype in your decision."
Apple scaled new heights as fellow technology heavyweight Facebook briefly plumbed new depths. The social network slid to a record intraday low of $18.75 on Monday before bouncing back to trade around $20 after Capstone upgraded the company's stock to buy from hold on Monday.
(Reporting by Edward Krudy, editing by Kenneth Barry)