A Court of Appeal decision has led to governments enacting legislation which requires consideration of Treaty principles in decision making.
Jurisprudence built up since 1986 - including Privy Council action - to protect Treaty rights shouldn't be ignored, Mr Piripi said.
"People like Sir Graham [Latimer], they mortgaged their homes to fight for section nine ... We won that right from the Privy Council and what fool would step away from a hard-fought for right like that?"
The Prime Minister has argued that the clause wouldn't work in a mixed ownership model of an SOE such as Meridian Energy where the Crown retains 51 per cent and private shareholders own the rest.
Mr Piripi said a Treaty clause could work.
"A lot of commentators obviously don't think that's possible. They think iwi and Treaty are going to detract from its commercial viability but that's just not true. Maori rights are very similar to the public rights. You put the two together and they can sit side by side and work."
Ngai Tahu's Mark Solomon has taken a non-committal position on the retention of the clause in new legislation. He said he'd be looking closer at the Government's three proposed options - keep the section, dump it or include a more specific Treaty clause - up for consultation.
"Ngai Tahu will join other iwi leaders in looking at the merits of each of these options and we will be consulting our people before reaching a final conclusion on the best approach."
The Maori Party yesterday issued a "primer" on the consultation, setting out the issues at question and its own position - that it preferred either to retain section nine or a new clause.
Maori Party co-leader Tariana Turia said she and Dr Sharples would meet iwi leaders tomorrow, separately from Mr Key.
Asked if she believed a compromise Treaty clause could be forged, she said, "let's wait and see".
"I can't for a moment imagine that unless they have something in place that protects the interests of iwi, they would be bold enough to just do what they like anyway. But who knows?"
Waitangi: What happens when
Saturday
12pm: Iwi Chairs Forum
Sunday
All-day entertainment at Treaty Grounds.
10am: Prime Minister John Key at Te Tii Marae.
11.30am: Labour Party at Te Tii.
3pm: Prime Minister to meet iwi leaders.
6pm: Dame Malvina Major Frankie Stevens concert.
Monday
5am: Dawn service at Treaty Grounds.
8am: Royal New Zealand Navy band at Treaty Grounds flagstaff.
12pm: 21-gun salute.