The Serious Fraud Office says it's investigating the affairs of Gisborne finance company Rockforte Finance.
Rockforte was placed into receivership in May 2010 owing 77 investors $3.25 million.
Rockforte was a participant in the Crown retail deposit guarantee scheme and the majority of investors were covered by it.
The Securities Commission and the Ministry of Economic Development are also looking at matters related to the company.
Rockforte is the seventh finance company that has been investigated by the SFO since 2007.