Eric Kirkpatrick was charged with first-degree murder but convicted of second-degree murder and handed life in prison with no chance of parole for 15 years for killing Ben Banky in 2008.
On appeal, Kirkpatrick's lawyer called for a 10-year parole eligibility, arguing that the trial judge didn't put enough weight on mitigating factors like the man's epilepsy and his psychological state at the time.
But a three-judge appeal court panel rejected the argument, ruling the sentence is fit.
Late last year, the B.C. Court of Appeal rejected Kirkpatrick's bid to have his conviction reduced from second-degree to manslaughter saying the murder was planned and deliberate.
Kirkpatrick, now 66, was arrested a couple of hours after the shooting and told police he killed his former boss because he'd ruined his life.