How does a company acquire rights to a trademark?

A trademark is any word, symbol, design, device, logo, or slogan that identifies and distinguishes one product or service from another.

To obtain trademark protection it is necessary for a person or a business to sell a product using the mark. Consequently, trademark rights are only acquired when the trademark is used in commerce. Additionally, it is recommended to register the trademark in order to obtain special rights in the event of infringement. Trademarks are protected by federal and state law. Trademark owners can register the trademark with the PTO (federal) or with the respective secretary of state. Trademark rights are acquired by being the first to use the mark in commerce. The first user of the mark on goods in commerce creates an association with consumers, and trademark laws are intended to protect the consumer by avoiding confusion and enabling companies to compete fairly.

Under the Trademark Law Revision Act of 1998 a trademark owner can apply for registration prior to using the mark, based upon the owner's bona fide intent to use (ITU) the mark. If the application is approved and published without opposition, the trademark owner is required to submit evidence that the mark is in use within a period of three years. Upon submitting this evidence the PTO will issue the trademark registration. Currently, trademark registration are protected for an initial 10-year period. The registrant may renew the registration for subsequent 10-year periods as long as the mark continues to be used in commerce.

The extend of trademark rights is affected by several factors. These include:
-Distinctiveness of the mark.

-The date of first use in commerce.
-The geographic area where the mark is used.
-The registration of the mark
-The goods or services associated with the mark

References:
[1] Stim, R. "Intellectual Property. Patents, Trademarks, and Copyrights" West Legal Studies.
[2] Black's Law Dictionary 5th ed., (West Publishing, 1979).