While trademarks and copyright protect company names and logos, there’s a special kind of copyright to protect colors. It wasn’t until 1985 that the first rulings were made in regard to color trademarks. Color trademarks are more difficult to obtain, and they oftentimes only apply to a certain sector. For example, Cadbury has a particular shade of purple it is recognized for. No other company can use this exact purple for chocolate products, but they can use it for anything from shoe lines to nutritional supplements. The general rule of thumb is that the color must be so strongly associated with the brand by the general public that it would not be functional for other companies to use.
All John Deere products have that same recognizable color of green, but the color itself is not protected. Their logo, consisting of a yellow deer with the green background, is trademarked, but other farmers, trailer companies, and field workers can paint their equipment the same color. The same goes for McDonald’s. Despite the red and yellow coloration of the logo being easily distinguishable as theirs, any company can use those colors. The trouble comes if they try to have a design involving a yellow arch and red background. There can be another burger chain that tries to use the same exact colors McDonald’s uses in their logo, but unless they use the same design, they are free and clear to do so.
Some companies have coverage on certain aspects, but not all of their products. Tiffany Blue, the robin’s egg blue color you see on every Tiffany bag or box, is a color that is trademarked for those purposes specifically. Their color trademark only applies to their packaging, and other companies can use robin’s egg blue for any other purpose. There are companies that have failed to obtain color copyright for their products, like pink for Pepto-Bismol and white for Good Humor.