Its Trademark Law in Australia.
For example Cadbury has a trademark protecting its purple (defined as pantone 2685C) from competitors in the chocolate industry. On the other hand Whiskas protecting its purple (defined as CKMY {40% C, 100% M) from competitors in the cat food industry.
Because its trademark law both only cover their specific industries so purple would be fair game if opened a business in another field, but despite the precise definitions used for the colours they would be able to argue that a competitor using a similar purple could cause confusion in the consumers and would effectively block out an area in the color spectrum.
einkorn@feddit.org 3 days ago
I.e. Deutsche Telekom tried to stop other companies from using magenta. However, the court ruled that DT can’t hold a patent on magenta as a whole, only their specific hue.
Ritter Sport is a sweets’ manufacturer famous for their square chocolate bars.