Tipped off by an informant, the ACCC sparked media controversy with last year's raids on the offices of Caltex, Shell and Mobil to inspect and copy documents.

However, after reviewing the material obtained, the consumer watchdog concluded there was "insufficient evidence" to bear out the original allegations and so has now closed the matter.

Two of the three oil companies, Caltex and Mobil, who were subject to the raids and subsequent investigation told the market that the ACCC decision vindicates their respective positions.

"The announcement is a vindication of the Caltex position that it was unwarranted for the ACCC to use the media to publicise its raid on the company on 23 April 2002," said Caltex managing director, Jeet Bindra.

Mobil Oil Australia chairman Robert Olsen said the company cooperated fully with the ACCC, however, the unprecedented publicity given to the unfounded allegations was distressing to the staff and damaged its reputation.

Mobile added it hopes that the ACCC will respect the principle of 'innocent until proven guilty', before publicising unproven allegations to the media.