The label on this Thornton Hall dress reads: "Design copyright of this garment is the property of Thornton Hall Mtg Ltd. Attempts to reproduce are forbidden 1988."
Thornton Hall’s success was to come at a commercial price though with some local manufacturers and home sewers copying the designs. Eventually the copying got to a point where owners Isabel Harris and Brian Hall decided to take legal action in a case that made New Zealand law history in 1988. The case was decided in Thornton Hall’s favour and contributed to the creation of the Copyright Act in 1994.