"All we know about is what's been leaked, and that's not good enough. Something as important as this needs to be debated openly in a democratic forum."
Mr Rosenthal was pleased with the turnout given he had only started organising the march a few days earlier. The participants were passionate about the issue so it was likely there would be more protests in future, he said.
NZ First MP Fletcher Tabuteau has sponsored a private member's bill called The Fighting Foreign Corporate Control Bill, which, if passed, would stop the Government signing international agreements which included investor-state dispute settlement clauses.
Prime Minister John Key has argued that the bill would "strike a dagger through the heart" of free-trade agreements such as the long-awaited deal signed last week with South Korea. Northland exporters would suffer if the bill was passed, he said.
Mr Key and National's Northland candidate Mark Osborne were also in Kerikeri on Friday but did not cross paths with the protest.
The TPPA is a proposed free-trade deal between a dozen Asia-Pacific countries including New Zealand, the US and Japan.