The decision veered from the Court of Appeal, which in 2016 deemed the misstatement to be immaterial information for investors.
The High Court will now have to work out whether the untrue statement caused a loss for investors.
"This means that a court must determine whether the effect of the untrue statement was such that the market value of the securities for which the investor subscribed would have been lower than the price paid if the misleading statement had not been made or, put another way, if the prospectus had complied in all respects with the Securities Act and the Securities Regulations," the Supreme Court decision said.
Feltex was floated on the stock exchange in 2004 at an issue price of $1.70 a share, but those shares were "effectively worthless" just 18 months later when the company was placed into liquidation.
Some 3639 former Feltex shareholders sought $185 million from former Feltex directors and IPO promoters.
The Supreme Court judges dismissed an appeal against First NZ Capital and Forsyth Barr as joint lead managers, saying those investment firms were not promoters under the act.
Former directors Timothy Saunders, Samuel Magill, John Feeney, Craig Horrocks, Peter Hunter, Peter Thomas and Joan Withers, sale promoter Credit Suisse Private Equity and vendor Credit Suisse First Boston Asian Merchant Partners now face the second tranche of the trial.