In July, a judge found Oki guilty on 13 felony counts that included theft, forgery, money laundering and use of a computer in the commission of the crime.
Oki formed the firm in 2010, along with four former Grant Thornton employees. News coverage of his sentencing said former partners called him an "evil person" who had ruined their lives.
He created fictitious persons, companies, contracts, IRS forms, invoices, financial documents, websites and e-mail addresses in claiming he had incurred expenses for services provided to clients. He made false entries in the firm's books and forged signatures of fictitious persons.
A Certified Fraud Examiner, Oki had served on the board of the Hawaii Society of CPAs for several years and was president of the University of Hawaii alumni association.