VICTORIAN THOROUGHBRED RACING'S LONG-RUNNING COBALT SAGA:

April 2014 - Victoria introduces cobalt threshold of 200 micrograms per litre of urine

December 2014 - Stewards announce positive cobalt tests for two horses trained by country-based father-son partnership of Lee and Shannon Hope (from races in June and July)

January 2015 - National cobalt rule comes into effect

- Caulfield trainer Peter Moody told of cobalt positive for one of his horses (from October 2014 race)

- A day later Flemington trainers Danny O'Brien (three horses from November 2014 races) and Mark Kavanagh (one horse from October race) told about positive tests

- News of cobalt positive for third Hope horse (from September 2014 race)

March 2015 - News of cobalt positive for fourth O'Brien horse (from December 2014 race)

June 2015 - Hopes, O'Brien and Kavanagh charged by Racing Victoria stewards, plus O'Brien and Kavanagh's vet Dr Tom Brennan

July 2015 - Moody charged

October 2015 - Hopes plead not guilty as Racing Appeals and Disciplinary Board hearing begins

November 2015 - Hopes found guilty of intentionally administering cobalt to affect the performance of three racehorses; Shannon Hope disqualified for five years and Lee Hope for three years

- Kavanagh and O'Brien plead not guilty as RAD Board hearing begins. Vet Brennan admits supplying substance called vitamin complex that was added to drips administered to the trainers' horses but says he didn't know it contained cobalt.

December 2015 - Moody pleads not guilty as RAD Board hearing begins; blames hoof treatment for cobalt levels

- Kavanagh, O'Brien and Brennan found guilty of intentionally administering cobalt to affect a racehorse's performance; Brennan

January 2016 - O'Brien disqualified for four years, Kavanagh for three years and Brennan for five years

March 2016 - Moody cleared of most serious charge of intentionally administering cobalt to affect a racehorse's performance; found guilty of lesser administration offence

- Moody suspended for six months (given 12-month suspension but half suspended for a year)

- Moody pulls pin on training career

August 2016 - Appeal by O'Brien and Kavanagh begins in Victorian Civil and Administrative Tribunal. Hopes' appeal partly overlaps. Brennan withdrew his appeal.

September 2016 - National cobalt threshold halved to 100mg per litre of urine; plasma threshold introduced

December 2016 - VCAT president Justice Greg Garde reserves his decision after 23 days of evidence

March 2017 - Garde dismisses charges against Kavanagh and O'Brien

June 2017 - Racing Victoria appeals VCAT decision in Court of Appeal on two points of law surrounding interpretation of rules of racing

November 2017 - Court of Appeal finds trainers not guilty of administration. Case to return to VCAT for decision on penalty for presentation.