An Ontario judge has thrown out the illegal stock-tipping convictions against former RBC Dominion Securities investment banker Andrew Rankin, and sent the case back to a lower court for a new trial.

In July 2005, Rankin had been convicted on 10 counts of giving illegal stock tips on pending mergers and acquisitions to Daniel Duic and sentenced to a six-month jail term.

Ranking was previously acquitted on 10 related charges of illegal insider trading.

In today’s ruling, Ontario Superior Court Justice Ian Nordheimer said a lower court judge failed to take into account inconsistencies in the testimony of Duic, the prosecution’s key witness.

Rankin, who was free on bail, had appealed the conviction and sentence.

The Ontario Securities Commission also appealed the sentence, seeking more jail time.

In a statement, the OSC said it will review the decision and reasons and consider its options.