The Financial Markets Authority is appealing the sentences handed down to the four Lombard Finance directors, including for cabinet minister Sir Douglas Graham.
In February, all four were found guilty in the High Court at Wellington of making misleading statements in documents seeking money from the public between December 2007 and April 2008, when Lombard was put into receivership, owing $111 million to about 3600 unsecured investors.
FMA spokeswoman Diane Maxwell confirmed the sentences would be appealed, but no other details were available.
It is understood the appeal was filed on Thursday afternoon.
Graham, Bill Jeffries, who is also a former justice minister, Lawrence Bryant and chief executive Michael Reeves, all filed appeals against their convictions in the Court of Appeal in Wellington earlier this month.
Graham, 70, was sentenced to 300 hours' community work and must pay $100,000 reparation.
Jeffries, 66, a lawyer, was sentenced to 400 hours' community work. He said he could not pay reparation and, even if he could, he had philosophical and principled objections to doing so.
Reeves, who founded the company, was sentenced to 400 hours' community work.
He could not pay reparation and Justice Robert Dobson said the sentence that otherwise would have been appropriate was reduced because of his ill-health and having sole care of two children and part-time care of a third.
Bryant, 68, was sentenced to 300 hours' community work and must pay $100,000 reparation. The owner of a small vineyard in Wairarapa, he said he would borrow money to pay.
Graham, who has faced calls for him to be stripped of his knighthood, said his appeal would question the convictions' findings on the extent of a non- executive director's obligations and a director's right to rely on competent advice. It would also assert that some of the Crown's evidence at the trial was hearsay.