The Serious Fraud Office says charges against the majority of failed finance firms it investigated is a good result.
The agency ended an investigation into the firms, following a decision not to prosecute Hanover Finance, as it could not be sure it would get a conviction.
That has upset some Hanover investors, who feel let down. About 13,500 investors were owed $554 million when Hanover suspended payments nearly five years ago.
But SFO acting chief executive Simon McArley said Hanover is still facing civil charges filed by the Financial Markets Authority.
He defended the record of the SFO, saying its work resulted in criminal prosecutions against nine of the 15 firms it looked at.
Now the Serious Fraud Office has finished its investigation, stockbroker Chris Lee says the way is clear for civil lawsuits and possible compensation for investors.
Mr Lee said about eight civil cases are already underway with compensation claims expected to total more than $1 billion.