A definition of what a trademark is a useful place to start in learning about trademark law. Trademarks are defined by 15 USC 1127: the term “trademark” includes any work, name, symbol, or device, or any combo thereof

(1) Used by a person, or (2) Intended to be used in commerce (3) To identify and distinguish his goods, including a unique product, from those manufactured or sold by others and to indicate the source of the goods, even if that source is unknown

Service Marks provide an analogous functions that trademarks do, for services. While registration is not necessary, it confers greater protection. Protection occurs upon use or upon registration which is premised on use.
Trademarks can protect your company’s brand, colors, reputation, even packaging that distinguish your business from competitors. In addition to your company’s name, its packaging and product designs can be trademarked. These are defined as your company’s “trade dress” or “product configurations”. These include the design and packaging of materials, but cannot be functional; they must be source-identifying (for example, what you are trying to protect relates back to your company’s name or brand, not the actual method of packaging). Trade dress and product configurations may be registered as “trademarks”, but in common use most are not registered because these are subject to protection under 15 USC 1125a. A common question asked with trademarks, is why bother registering? The quick answer is registered marks confer priority and provide enhanced protection over unregistered marks. There are 2 bases for eligibility for trademark registration, the “used in commerce” (15 USC 1051a1) requirement and the “Bona fide intention/good faith to use TM in commerce” (15 USC 1051b1).

There are several benefits of registration. The first is that your registered mark provides constructive notice of ownership to other people that may try to assert your trademark. In addition, your registered mark enjoys presumptions of validity, ownership, and the registrant’s exclusive right to use the mark nationwide. In addition, there is the possibility of achieving “incontestable” status after 5 years, and registrants do not bear the burden of establishing non-functionality. You also gain the right to prevent the importation of infringing foreign goods. In addition, unregistered marks are subject to geographic limitations, since they are established only in the area of use. Registering automatically confers nationwide protection; for marks used in different areas at the same time, the trademark office has a special process called “interferences” and concurrent use may be possible, with restrictions.

Unregistered marks receive protection under the Lanham Act. To establish protection under the Act you need “relatively substantial use” and you must be first in time to use the mark (this is called establishing priority). Without registration, this trademark ownership does NOT confer nationwide protection unless you can establish nationwide use, but non-registered users of trademarks can claim priority over registered marks if they made continuous use of the mark in a geographical area before registration.