Judge Datuk Zaleha Yusof, in her decision, ruled that based on the MAU constitution, Karim was not a member of the union.
"The disciplinary proceeding meted against him was a serious matter and in view that he is not a union member, MAU cannot take action against him," she added.
Last April 1, Karim, who is also the Melaka Athletics Association vice-president, filed an originating summons against MAU to challenge his six-year suspension by the Union.
In the originating summon, Karim had asked the court to decide if the MAU had the authority to order his suspension although he was not a MAU member during the said period in accordance with the MAU constitution that was amended on July 25, 2011.
Karim was suspended by the MAU for allegedly assisting six national athletes to snub a doping test by the National Sports Institute (ISN) in 2011.
The MAU which set up a panel headed by former Appeals Court judge Tan Sri V.C George to investigate the matter, had allegedly found Karim guilty of the offence.
Karim, who was represented by lawyer Didiana Zakaria, was at the court.
MAU was represented by lawyers Alex De Silva and Adlan Hadi Mohamad Yusof.