1208.03 Procedure Relating to Possibility of Interference 
Section 16 of the Trademark Act, 15 U.S.C. §1066, states that, upon petition showing extraordinary circumstances, the Director may declare that an interference exists when application is made for the registration of a mark that so resembles a mark previously registered by another, or for the registration of which another has previously applied, as to be likely, when used on or in connection with the goods or services of the applicant, to cause confusion or mistake or to deceive. No interference shall be declared between an application and a registration that has become incontestable. These cases are extremely rare and are generally limited to situations where a party would be unduly prejudiced without an interference, such as where it would otherwise be required to engage in a series of opposition or cancellation proceedings involving substantially the same issue. See TMEP §1208.03(b).
An interference will not be declared except upon petition to the Director. All petitions or requests for interference should be forwarded to the Office of the Deputy Commissioner for Trademark Examination Policy for decision. The examining attorney does not make a determination on a request for interference.
See TBMP Chapter 1000.
1208.03(a) Procedures on Request for Interference
The request for interference should be in a separate document in the form of a petition, and should be captioned as a petition. The petition fee indicated in 37 C.F.R. §2.6 should accompany the request. A petition to declare an interference should not be filed before the application has been examined and the mark has been found to be registrable but for the existence of one or more conflicting pending applications.
A request for interference does not make an application "special" or alter the normal order of examination.
See TBMP Chapter 1000.
1208.03(b) Decision on Request for Interference
The Director will declare an interference only upon a showing of extraordinary circumstances that would result in a party being unduly prejudiced in the absence of an interference. The availability of opposition and cancellation procedures provides a remedy and ordinarily precludes the possibility of undue prejudice to a party. Id. The request for interference must show that there is some extraordinary circumstance that would make the remedy of opposition or cancellation inadequate or prejudicial to the party’s rights. See In re Family Inns of Am., Inc., 180 USPQ 332, 333 (Comm’r Pats. 1974). The potential need to file two notices of opposition that could be consolidated if the issues were sufficiently similar is not considered an extraordinary circumstance that will unduly prejudice a petitioner without an interference. The fact that an earlier-filed application based on §1(b), §44, or §66(a) has been cited against a later-filed application based on use in commerce under §1(a) also is not an extraordinary circumstance that warrants declaration of an interference. An opposition proceeding is the proper forum for determining priority between an applicant and another party. Priority for purposes of examination of an application is determined by filing date. 37 C.F.R. §2.83(a); TMEP §1208.02(a).
Although §16 of the Act permits the declaration of an interference between an application and a registration, the practice of declaring an interference in these cases has been discontinued because the applicant cannot obtain a registration if the interfering registration remains on the register; therefore, even if the applicant prevailed in the interference, the applicant would still have to petition to cancel the interfering registration. See In re Kimbell Foods, Inc., 184 USPQ 172, 172 (Comm’r Pats. 1974); Ex parte H. Wittur & Co., 153 USPQ 362, 362-63 (Comm’r Pats. 1966); 37 C.F.R. §2.96.
See TBMP Chapter 1000.
1208.03(c) Procedure When Interference Is to be Declared
If the Director grants a petition requesting an interference, the examining attorney must determine that each mark is registrable but for the interfering mark before the interference will be instituted.
All marks must be published for opposition before interference proceedings are instituted. Id. If possible, the marks should be published simultaneously.
Each application that is to be the subject of an interference must contain the following statement to be printed in the Official Gazette:
This application is being published subject to declaration of interference with:
Serial No.:
Filed:
Applicant:
(Address, if there is no attorney)
Attorney and Address:
Mark:
The examining attorney should prepare the statement.
If an application that is published subject to interference is opposed by a party other than the applicant(s) in the interfering application(s), the opposition will be determined first. If still necessary and appropriate, the interference will be instituted. If an opposition is filed by the applicant in the interfering application, the rights of the parties will be determined in the opposition proceeding, and the interference proceeding will not be instituted.
If, during the pendency of an interference, another application appears involving substantially the same registrable subject matter, the examining attorney may request suspension of the interference for the purpose of adding that application. If the application is not added, the examining attorney should suspend further action on the application pending termination of the interference proceeding.
See TBMP Chapter 1000.