Employment issues and procurement decisions are among the most frequent concerns raised with the new federal integrity watchdog.
National Anti-Corruption Commission CEO Philip Reed told a Senate estimates hearing the commission had received 1494 referrals since it began in July.
Of those, 61 per cent had been excluded as "out of jurisdiction" as they did not involved a commonwealth public official or raise a corruption issue.
He said frequent themes were employment or recruitment-related issues and procurement decisions.
The commission has opened nine preliminary investigations, to help decide whether there is a corruption issue that should be further investigated.
It has opened four new investigations, and decided to refer one corruption issue to a Commonwealth agency to which the issue relates for investigation and report.
The NACC is working on six active investigations inherited from the former Australian Commission for Law Enforcement Integrity.
Mr Reed declined to go into any detail about the investigations, as it could prejudice operations or unfairly damage reputations.
