A conspiracy to bribe foreign officials will cost the technical services firm that picked up on it an extra $2 million.
American company Jacobs Group self-reported breaches it identified in due diligence while taking over Australian consulting group Sinclair Knight Merz.
That company previously worked on major national projects including highways, desalination plants and warships before it was purchased by Jacobs in 2013.
Jacobs was fined $1.35 million in June 2021 after pleading guilty to a conspiracy to bribe public officials in Vietnam between 2010 and 2012.
A $US280,000 provision for bribes was disguised in the subsidiary's spreadsheets as "PM Support".
More than $A200,000 was eventually paid out.
The eventual, million-dollar fine was determined against a maximum penalty of $11 million, but in subsequent appeals it emerged the maximum penalty should have been more than $30 million.
The imposed fine was heavily discounted due to Jacobs' early guilty plea and the support it provided during its own prosecution.
But the company argued it should have received an even greater discount as the NSW Supreme Court reconsidered the penalty.
Justice Ian Harrison said in his decision on Wednesday that Jacobs argued its evidence over several years had allowed the prosecution to pursue the charges to which it later pleaded guilty.
However, he retained the discount on sentencing as an accurate reflection of Jacobs' exemplary conduct, noting any greater discount risked diluting the deterrent effect.
Justice Harrison imposed a fine of $3.375 million, exceeding the earlier fine by more than $2 million.
Jacobs' 2021 prosecution also included fines of $67,500 and $54,000 for a separate bribery conspiracy involving Sinclair Knight Merz in the Philippines and an earlier part of the Vietnam conspiracy.
