Dmitri Kossyrine and Ivgeny Vorobiov were charged with first-degree murder in the death of Glen Davis.
Vorobiov was found guilty, but after four days of deliberations, the jury couldn't reach a verdict in the case of Kossyrine and the judge declared a mistrial.
"It does not bring Glen Davis back to his family, his friends and his many endeavours," Det. Sgt. Peter Moreira, who led the investigation into Davis's death, said outside court. "There is nothing positive about this, except that there is some accountability for the actions of Ivgeny Vorobiov."
Davis, a 66-year-old multimillionaire, was shot and killed in an underground parking lot in May 2007 following a meeting with the World Wildlife Fund, one of many environmental causes he supported financially.
The Crown alleged Kossyrine was the middle man in a murder-for-hire plot masterminded by Davis's godson, and Vorobiov was the shooter.
The defence argued Vorobiov went to the garage with a loaded gun intending to kill Davis, but changed his mind at the last minute, and that it was another man, Jesse Smith, who pulled the trigger.
Smith denied shooting Davis and pleaded guilty last year to being an accessory after the fact to murder.
Davis's godson Marshall Ross pleaded guilty to first-degree murder in October, admitting he plotted the killing.
Ross owed $2.5 million to Davis's company, something he was struggling to repay.
The 41-year-old Ross is serving a life sentence.
"Glen was a very close friend and one of the most generous men I ever met," Peter Quinn, a longtime friend of Davis, said outside the court. "As a group, we are glad that three of the four accused have been dealt with and it's over."
(CFRB, The Canadian Press)