Maori Council lawyers say they are responding to new, written Crown evidence presented to the Waitangi Tribunal hearing into water rights.
Although the tribunal is no longer sitting in public, council lawyers are sifting through hundreds of pages of submissions.
And the lead lawyer for the Maori Council, Felix Geiringer, says the lawyers have a Wednesday deadline to reply in writing to the inquiry.
The Waitangi Tribunal's next step will be to make a recommendation in response to the claimants' call that the Crown should delay its sale of shares in the hydro power generator, Mighty River Power.
The Maori Council filed a Waitangi Tribunal urgent claim as a result of the Crown's plan to sell up to 49% shares in selected state-owned power enterprises.
Once that has been published, the inquiry will compile a report on all the evidence presented so far.
There'll then be a second round of hearings into water rights and interests, before a full tribunal report is drawn up.
Separately, a co-chair of the Maori Council, Maanu Paul, says the Government's proposed bonus share scheme is a last ditch attempt to try and entice people to invest in state-owned assets.
Prime Minister John Key says individual New Zealand investors will be guaranteed a purchase of up to $2000 worth of shares - which will begin with Mighty River Power.
Under the loyalty scheme, investors will be given bonus shares if they hold on to their original investment for a minimum period - probably three years.
Mr Paul says Mr Key's proposal appears to be a last-ditch stand.