The Australian Competition and Consumer Commission has completed its investigation into three major oil companies, Caltex, Shell and Mobil, and associated petroleum distribution companies. It will take no further action.

"The ACCC began its investigation after receiving information from an anonymous informant raising serious claims of possible breaches of the Trade Practices Act 1974 in this crucial industry", ACCC Chairman, Professor Allan Fels, said today.

"The ACCC assessed this information and concluded that it needed investigation.

"The ACCC concluded that it was both necessary and lawful to enter various oil company sites, exercising its powers to inspect and copy documents. This view was confirmed by an independent Senior Counsel. Substantial amounts of material were copied and removed and were analysed over the following months.

"At the time, the ACCC indicated that lengthy economic and legal analysis of the numerous copies of documents would be required. Whilst the ACCC indicated that it was unclear whether a breach of the Act had occurred, it believed that the allegations needed to be thoroughly investigated.

"Despite calls from the ACCC to do so, via advertisements and media statements, the informant has not come forward.

"At the time the matter became public, the ACCC said it would publicly announce the outcome of the investigation.

"After reviewing the material obtained, the ACCC has concluded that there is insufficient evidence that would bear out the original allegations. It has now closed the matter".