Jockeys Shane Kelly, Josh Byrne, Fran Ferris and David Nolan and trainer Phil McEntee have received bans for breaches of the Rules of Racing.
A disciplinary panel of the Horseracing Regulatory Authority ruled the five had illegally passed on information.
Kelly was banned for 12 months, Nolan for nine, and Byrne for four. A ruling on Ferris, already serving a two-year ban, was postponed.
McEntee will not be allowed to send out any runners for 12 months.
The five were primarily found to have broken Rule 243 by communicating to Ajaz Khan for material reward, gift, favour or benefit in kind, information that was not publicly available.
The riders were also judged to have misled HRA officials in an overt act, with Byrne also guilty of providing inaccurate information.
Kelly's appeal against the finding of a breach of Rule 157 - which deals with riding a horse to lose in the knowledge that it was being laid to lose or having received reward - was upheld.
I will be able to pick up my career after the suspension finishes
The charge related to his ride on Local Fancy at Warwick in March 2005.
The 28-year-old will not be allowed to race-ride for one year, but can still work in racing and will continue his association with Newmarket trainer Jeremy Noseda among others.
Kelly said: "I will think about an appeal, but will wait to see the full reasons for the panel's decisions before deciding.
"They have cleared me of stopping a horse, but I am still disappointed to get
suspended for a year as I don't think the evidence was there, and I wish the
press were allowed in to the inquiry to see the evidence.
"I will be able to pick up my career after the suspension finishes. I was off
for nine months recently with a broken leg and came back from that.
"Racing and working with horses is what I love and is what I will continue to
do. I can still go racing and will keep on going."
Byrne was found to be in breach of all four counts of passing information, Ferris in breach of nine counts regarding his own mounts and seven of those ridden by Nolan.
McEntee was in breach on all seven counts and Nolan on all eight.
Ferris was also found guilty of breaching Rule 157 on five occasions.
He was additionally charged with hindering or obstructing a person duly approved and authorised by the HRA engaged in carrying out an investigation in connection with horseracing.
Khan is currently disqualified from racing and the HRA disciplinary panel ruled an application to relax this should not be entertained for 10 years.