Oil exec handed largest ever fine over contract rigging

These attempts, over lucrative natural gas tenders released by energy behemoth Shell, took place at a Brisbane restaurant and a luxury hotel both by the river between 2017 and 2019.

The firm was fined $5 million and Mr Ashton $1 million respectively on Thursday.

The penalty against Mr Ashton is the highest for a competition law breach by an individual in Australia.

"Cartels represent a significant threat to competition in the Australian economy, especially in such an important and sizeable industry,"  Australian Competition and Consumer Commission chairwoman Gina Cass-Gottlieb said on Thursday.

"As this case demonstrates, if you try to make cartel agreements with competitors, you will be met with strong enforcement action by the ACCC - even if your attempts do not succeed."

Qteq's primary business was the sale, installation and servicing of pressure gauges to coal seam gas producers and was considered a market leader, counting gas giant Santos as its biggest customer.

The Federal Court found the company and Mr Ashton attempted to coax competitor Pro-Test Pty Ltd three times, and rig and drilling company Easternwell twice, into cartel arrangements.

Qtel, its chairman "and others in a like position, must receive the message loud and clear that the illegal response they attempted to implement is unacceptable and cannot be tolerated," Justice Robert Bromwich said in his judgment on Thursday .

"After an attempt at one illegal remedy did not work, another was tried."

Mr Ashton, who the ACCC described as "a man of considerable wealth" with almost $25 million in assets to his name, did not show "any sign of contrition," the judge said.

Justice Bromwich specifically fined him $1 million because he was "the driving force for most of the conduct by Qteq, and stood to benefit from that conduct".

An order was made to ensure Mr Ashton cannot make an insurance claim to help cover his fine.

Legal costs were also awarded against him and the company.