The Commerce Commission has filed proceedings under sections 27 and 36 of the Commerce Act in the Auckland High Court against Winstone Wallboards, a subsidiary of Fletcher Building that manufactures and supplies GIB-branded plasterboard. The Commission alleges that Winstone's use of retroactive tiered rebates in its plasterboard supply agreements with building supplies merchants between 2017 and 2022 breached the Commerce Act.
Commission Chair, John Small, says that while historical, the Commission considers the conduct to be serious and warrants proceedings under the Commerce Act. "While the use of rebates can deliver benefits, retroactive tiered rebates can also harm competition when they're used by a supplier with substantial market power because they can reduce the ability of smaller suppliers or new entrants to compete.
"In this case, we allege Winstone used retroactive rebates to damage competition, ultimately leading to consumers paying higher prices."
As the proceedings are before the Court, the Commission cannot comment further at this time.
Background
The use of retroactive rebates was identified as a potential barrier to competition in the Commission's market study into residential building supplies, completed in December 2022.