Legal Definitions - complementary goods

Complementary Goods

In a legal context, complementary goods are products that are commonly purchased and used together because one enhances or is necessary for the use of the other. These goods are often designed to work in conjunction, and consumers typically associate them as a pair or a set.

The concept of complementary goods is particularly relevant in trademark law. If two different companies use similar brand names or logos on products that are complementary, consumers might mistakenly believe that the goods come from the same manufacturer or are officially endorsed by the original brand. This potential for confusion can lead to legal disputes over trademark infringement.

• Example 1: Gaming Consoles and Proprietary Games

  Imagine a popular video game console, such as the "PlayStation 5," and the exclusive video games designed specifically for it. The console is largely useless without games, and the games cannot be played without the console. They are complementary goods. If a different company were to sell "PlayStation-like" games with a logo strikingly similar to Sony's, consumers might be confused into thinking these games are official Sony products, potentially leading to a trademark dispute.

• Example 2: Electric Toothbrushes and Replacement Brush Heads

  Consider a specific brand of electric toothbrush, like "Oral-B," and its corresponding replacement brush heads. While the toothbrush handle is the primary device, it requires the brush heads to function as intended for oral hygiene. These brush heads are designed to fit only certain models of the "Oral-B" toothbrush. If another company produced replacement brush heads with a very similar name or packaging design, consumers might mistakenly buy them believing they are genuine "Oral-B" products, which could constitute trademark infringement.

• Example 3: Smart Home Hubs and Compatible Smart Devices

  Think about a smart home hub, such as "Amazon Echo" (which uses Alexa), and various smart devices like light bulbs, thermostats, or door locks that are advertised as "Works with Alexa." While the hub can function independently to some extent, its primary value often comes from its ability to control and integrate with these complementary smart devices. If a competitor launched a smart home device with a brand name or logo that closely resembled "Alexa" and marketed it as compatible, consumers might assume it's an official Amazon product or endorsed by Amazon, creating potential trademark confusion.