Smerdon and Webb both train under the Aquanita Racing banner at Caulfield, one of the larger managers of thoroughbred racehorses in Australia. Vasil used to train for the same operation, which provides managerial services and shared administration for a small group of trainers
Birchley is based in Queensland but has frequented Aquanita stables on visits to Victoria.
Pennuto is currently serving a nine-month ban for illegally stomach-tubing a horse and used to work for Vasil.
Greg Nelligan and Garland are registered stablehands employed by Aquanita. Denise Nelligan works in the Aquanita office.
Aquanita directors, including Melbourne Racing Club chairman Mike Symons, have steadfastly denied any knowledge of corrupt behaviour.
Symons has not been charged, nor is suspected of any wrongdoing.
The Herald Sun reports stewards have gathered significant evidence of systematic doping and related betting activity.
The charges stem from a wideranging investigation into the alleged attempted treatment of Smerdon's mare Lovani at Flemington on October 7.
Information uncovered during the case over the past three months paints a scandalous picture.
Authorities last year moved to crack down on illegal race-day treatment, targeting stables suspected of using bicarb drenches within hours of a race to get an unfair advantage.
The drenches combat the build up of lactic acid, reducing fatigue - an edge critical in athletic contests.
One of RV's integrity initiatives included ordering horses to arrive on course an hour earlier, reducing the window for cheating.
The Herald Sun understands RV's compliance assurance team had Smerdon's staff in its sights as champion mare Winx took to the track for the Turnbull Stakes on October 7.
Integrity staff allege float driver Greg Nelligan was observed using a plunger containing a paste on Lovani after taking her into an enclosed stabling box at Flemington.
Nelligan was apprehended and the plunger was immediately confiscated.
The incident took place at 3.08pm - as Winx held the attention of virtually everybody at Flemington - timing integrity staff believe was deliberately used as a ploy to escape scrutiny.
But compliance assurance officers and undercover staff were strategically stationed around the stabling area because of suspicions regarding the Smerdon stable.
Nelligan was watched from the moment he walked Lovani into the box, closing the door behind him as he entered the enclosure. Lovani, who was due to contest the Paris Lane Handicap at 5.45pm, was scratched as stewards launched an inquiry. They interviewed Smerdon, Nelligan, Jim Cook and Garland before taking possession of Nelligan's mobile.
Intelligence provided by at least two of the eight charged personnel also helped stewards uncover what is believed to be entrenched rorting.
The paste contained in the plunger was analysed but the results have not been released.
During the subsequent investigation, thousands of text messages were uncovered - some with specific details of instructions to "top up" certain horses.
