The Commerce Commission says New Zealand's inability to jail cartel ring leaders may be making the country attractive to them.
The French firm Schneider Electric Industries has been fined more than $1 million after admitting to its part in the cartel in the electricity industry.
The chair of the Commerce Commission, Paula Rebstock, says jailing cartel leaders should be considered.
The commission took Schneider Electric to court after a member of the cartel exposed the operation, which had targeted New Zealand.
The company admitted its involvement in the cartel, which sought to control the market for components used in electricity transmission and, in effect, caused power companies and consumers to pay more.
The High Court in Auckland also ordered Schneider Electric to pay costs of $50,000 to the Commerce Commission.
Ms Rebstock says they are continuing proceedings against two other companies involved in the cartel.