Several factors are considered in determining whether a trademark has been copied, such as use, intention and effect. A trademark protects businesses and consumers by identifying the source of a particular brand or product. Think of the Apple logo – when you see an apple with a bite out of it and a single leaf, you automatically associate the design with Apple’s brand. Trademark infringement occurs when a similar name or design causes confusion among consumers.
Registering your trademark with the U.S. Patent and Trademark Office is helpful but not necessary. Even if you don’t register, you can prevent others from using your trademark or one similar to it. Under the law, you are entitled to trademark protection simply by using your brand name or logo in packaging, advertising, marketing and other commerce. Registration doesn't guarantee that others won’t use your names or designs, but it does create a record of what's yours.
Similarity is one factor weighed in trademark infringement. If another business uses a name or design similar to yours, it may be infringement. The legal test is whether the name or design is so similar that consumers might have difficulty distinguishing your product from that of a competitor. If so, the similarity may be wrongful copying.
Actual confusion isn’t a requirement of trademark infringement. The possibility of confusion is often enough to establish infringement. Actual evidence of confusion strengthens your case but isn't necessary.
A company or individual may be able to use your trademark in limited situations without infringing on the mark under the doctrine of fair use. Think of Apple again: the apple is a common fruit, so a company can use an apple in its own trademark as long as it isn't confusing to consumers. Fair use also includes comparisons, such as when a company compares its product to yours in advertising. Another fair use allows companies and individuals to parody your product or trademark to make a point about values or ideas.