Apple has lost its title as the world's most valuable publicly listed company after its shares continued to fall last week.
Oil company Exxon Mobil has regained the top slot after Apple shares fell 2.4%, following a 12% drop on Thursday, the BBC reports.
Apple posted disappointing iPhone sales figures on Wednesday and has seen its shares fall 37% since their record high last September.
Exxon became number one in 2005, traded places with Apple during 2011, and had been number two since early 2012.
At the close on Wall Street, Apple had a market value of $US413 billion against Exxon's $US418bn.