An investigation has found no evidence any Ministerial Services staff leaked information to the media about Winston Peters being overpaid superannuation for several years.
The Department of Internal Affairs interviewed Ministerial Services staff and searched digital records as part of it investigation.
The probe found five Ministerial Services employees had received the information before it was reported by media but there was no evidence they provided the information to any third parties, a Department of Internal Affairs spokesperson said.
"The Department takes privacy seriously, and upholding the confidentiality of information forms part of the Code of Conduct all employees sign.
"If further information comes to light, the Department will undertake further inquiries as necessary."
Two other government agencies - the Ministry of Social Development and Inland Revenue - have also denied any of their staff were involved in the leak.