Former Tennis Australia director Harold Mitchell overstepped the line in negotiating television rights for the 2013 Australian Open, the Federal Court says.
Mr Mitchell was found to have breached his duties as a director on three occasions ahead of the grand slam tournament.
This included passing on information to Seven West director Bruce McWilliam in 2012. Seven West won the contract for the Open.
The financial regulator took Mr Mitchell and former Tennis Australia president Steve Healy to court over the saga.
Justice Jonathan Beach on Friday threw out the bulk of the Australian Securities and Investments Commission's allegations against Mr Mitchell, barring three instances. He also threw out the entire case against Mr Healy.
"Mr Mitchell stepped over the line in his dealings with Mr McWilliam," Justice Beach found.
"There were some things that he communicated to Mr McWilliam that he ought not to have done, particularly in the latter part of 2012."
But the judge found none of this caused any damage to Tennis Australia.
"I reject ASIC's case that Mr Mitchell gave Seven information with a view to assisting them to win the contract and worked together with Seven to give Seven the inside running to get this contract," Justice Beach said.
"None of this was motivated by anything other than Mr Mitchell's perception that he thought that it was in the interests of TA that a deal with Seven should be stitched up sooner rather than later.
"His contraventions are far narrower in scope than ASIC would have liked it."
Mr Mitchell "was one of those characters who often liked to and did get his own way", Justice Beach noted. He also dubbed Mr McWilliam a "colourful character".
The judge wasn't prepared to slap the former director with a corporate ban but did propose a modest fine.
The extent of that fine will be determined when the case returns to court at a later date.