MRP is expected to become the 4th or 5th ranked company in the top 20 of the New Zealand stock exchange when it lists.
The Government is looking to float 49% of Mighty River Power, with estimates the 686 million shares will sell for between $2.35 and $2.80, in a bid to raise as much as $1.9 billion.
On Friday, the Financial Markets Authority announced it was satisfied the 256-page MRP prospectus contained the information potential investors require to make an informed decision, a move which formally releases the offer to be presented to the public.
MRP's chief executive, Doug Heffernan, is completing a nationwide roadshow for stockbrokers, before leaving for three weeks to drum up support from overseas institutional investors, in Australia, Singapore, Hong Kong, London and the United States.
The extent and percentage of the book-build for institutional investors would be decided by the Crown, Mr Heffernan said in Dunedin last week.
He said about $1 billion of MRP's assets are geothermal-based, making it the 13th largest geothermal generator in the world, with initial scoping projects under way in Chile and the United States.
State-owned Enterprises Minister Tony Ryall said New Zealanders had three weeks to apply for shares, until May 3, saying the general offer was only open to New Zealanders, to put them at the front of the queue to achieve widespread New Zealand ownership.
