Robert Deer was convicted of manslaughter in the death of Jack Beauchamp in January 2006.
Beauchamp was shot six times in a hallway of his company's offices, Morbank Financial.
Deer sent Mohamed Karim to "send a message" to Beauchamp after a multimillion-dollar property deal fell through, but both said they didn't intend for Beauchamp to die.
Karim was found guilty of second-degree murder and will be sentenced in January.
Deer only has to serve 4 1/2 years of his 16-year sentence after getting credit for time already served.
His lawyer, Jim Lutz, says they were expecting a less severe sentence, and he had previously pushed for Deer to be let out on time served.
Outside court, Beauchamp's widow Debra said it was good news that Deer would be spending more time behind bars.
With Karim facing a mandatory sentence of life in prison, the only thing left is to determine parole eligibility, so Debra said "it ends here."