One of Australian racing's darkest chapters, the affair was described at the time as "probably the biggest scandal and the most widespread investigation in the history of Australian racing" of which prominent Victoria trainer Robert Smerdon was said to be the ringleader.
Smerdon was banned for life, and fellow trainers Stuart Webb and Tony Vasil disqualified for 18 months as well as four other staff with links to Aquanita Racing for their role in the doping of horses, many involving the use of milkshakes or 'top-ups', on raceday between 2010 and 2017.
Having considered 395 instances of potential doping, Racing Victoria stewards have now concluded 81 starters should be considered for disqualification based on actual administration findings, of which 24 were winners.
The races under scrutiny include the victory of Politeness in the 2015 edition of the G1 Myer Classic at Flemington plus two wins for champion jumper Black And Bent.
They have written to the managing owner of those starters inviting them to show cause by next month as to why their horse should not be disqualified.
Jamie Stier, the authority's executive general manager – integrity services, said: "This is a unique and complex case which required the stewards to consider tribunal findings and available evidence to them in cases which ultimately saw people disqualified for improper practice not swab samples.
"Having considered all the facts, the stewards are satisfied that they can clearly identify 81 starters that were the subject of a prohibited administration and thus they have today written to the managing owners of these horses at the time of the relevant races, or their representatives, to afford them the opportunity to state why their horse ought not be disqualified from the race in question.
"The Stewards are not satisfied that the other 313 starters ought be considered for disqualification as the available evidence did not definitively demonstrate that those horses were the subject of a prohibited administration on the given day."
Central to the findings in the case were 1,000 texts between those involved. Stier said that although these provided clear evidence of wrongdoing, it was not possible to determine the identity of every horse that was doped.