Law firm Chapman Tripp is giving a thumbs down to a proposal to make all big companies file financial statements publicly.

The proposal in a Ministry of Economic Development (MED) discussion document applies to companies meeting any two of three criteria -- total assets of at least $10 million, consolidated annual revenues of at least $20m and, or at least 50 fulltime equivalent employees.

The move may apply to partnerships like law and accounting firms. It would apply to companies owned by private families like the Talley and Todd families.

Currently all companies prepare accounts but only those that seek funds from the public and overseas owned companies have to make them public.

"They made cutting room floors for ideas like this," said Chapman Tripp partner Pip England.

MED's rationale is that there is "a broad societal interest" in the financial health of large entities.

The move to make "economically significant" non-issuer companies file general purpose financial accounts each year to the registrar of companies follows similar moves in Australia.

MED estimates that 2000 companies could be affected by the rule change.

Chapman Tripp said a similar idea was shot down in New Zealand in 2005. It raised significant concern among private businesses at the time.

At that time it was argued that it would be a disincentive to invest in New Zealand, it was an unwarranted intrusion of privacy and an unnecessary imposition of compliance costs.

"A lot of people make a conscious decision not to go into the public domain," Mr England said.

Mr England acknowledged that Chapman Tripp as a firm could be caught by the proposed change if extended to partnerships.

"But that is not our motivation. We were just as strongly opposed in 2005 although there was no policy intention at that time to extend the requirement beyond companies," he said.

MED is proposing that New Zealand follow Australia's lead and implement a grandfathering provision to exempt entities already in existence when new regime comes into effect.

"That will provide some comfort to those who qualify for the exemption but it does not even begin to address the principled question of whether the proposal has any intrinsic merit which, in our view, it does not," Mr England said.