Labour leader David Shearer is standing by his position that a loyalty scheme for people who buy shares in Mighty River Power is a taxpayer subsidy for investors.
The company is to be partially sold and the Government is offering bonus shares to buyers who hold their shares for a period - probably three years.
A stockbroker who was involved in the partial privatisation of Queensland's rail network says a similar scheme did not cost the state government there very much compared with the value it got from the sale.
But Mr Shearer still believes the Government would be subsidising investors with this scheme.
He told Morning Report he thinks people will wait to get the loyalty bonus and then sell, making extra money off the taxpayer.
Brisbane stockbroker Philip Lee of RBS Morgan says bonus shares forced foreign financial institutions to pay more for their shares to outbid demand from domestic investors.
He says a similar scheme in New Zealand could increase the price the Government gets for its shares.