The Lanham Act states:
"§ 2 (15 U.S.C. § 1052). Trademarks registrable on the principal register; concurrent registration
No trademark by which the goods of the applicant may be distinguished from the goods of others shall be refused registration on the principal register on account of its nature unless it—
* * *
(d) Consists of or comprises a mark which so resembles a mark registered in the Patent and
Trademark Office, or a mark or trade name previously used in the United States by another and not abandoned, as to be likely, when used on or in connection with the goods of the applicant, to cause confusion, or to cause mistake, or to deceive . . ."
Some marks are not registered in the USPTO although they have been previously used in the United States and are not abandoned - - it may be a mark protected by common law or registered in a state, or it may be a trade name which can not be registered in the USPTO. The Applicant must verify that it has the absolute right to use the mark. But the Lanham Act specifically says that such marks may not be registered with the USPTO
However, Section 1207.03 of the Trademark Manual of Examining Procedure provides with respect to “Marks Previously Used in United States but Not Registered” that:
"As a basis for refusal, §2(d) refers not only to registered marks but also to 'a mark or trade name previously used in the United States by another and not abandoned.' Refusal on the basis of an unregistered mark or trade name has sometimes been referred to as refusal on the basis of a 'known mark.' This provision is not applied in ex parte examination because of the practical difficulties with which an examining attorney is faced in locating “previously used” marks, and determining whether anyone has rights in them and whether they are “not abandoned."
I recommend the the MTEP be changed so that the Examining Attorney must do an "online" search (for example, a Google search) to see if there are any relevant marks NOT registered or filed with the USPTO. If one or more relevant marks are found by the Examining Attorney by such an online search, the Examining Attorney can place the "burden of persuasion" on the Applicant to show the mark is no longer used or that it will not cause confusion, cause a mistake or deceive. If this approach is adopted, it will better protect the legal rights of those who have not registered with the USPTO and the extra effort required of the Examining Attorney will be minimal.