In vacating the Board's decision, the Federal Circuit enumerated the Du Pont factors that must be considered in a finding of likelihood of confusion, namely (1) the similarity/dissimilarity of marks in their entireties as to appearance, sound, connotation and commercial impression; (2) similarity/dissimilarity and nature of the goods/services as described in an application or registration or in connection with which a prior mark is in use; (3) similarity/dissimilarity of established likely-to-continue trade channels; (4) conditions under which and buyers to whom sales are made, i.e., "impulse" v. careful, sophisticated purchasing; (5) fame of prior mark (sales, advertising, length of use); (6) number and nature of similar marks in use on similar goods; (7) nature and extent of any actual confusion; (8) length of time during and conditions under which there has been concurrent use without evidence of actual confusion; (9) variety of good on which a mark is or is not used (10) the market interface between applicant and the owner of prior mark (11) the extent to which applicant has a right to exclude others from use of its mark on its goods (12) extent of potential confusion, i.e., whether de minimus or substantial (13) any other established fact probative of the effect of use. The court reasoned that the Board erred in failing to address Guild's argument and evidence related to DuPont factor 8. Particularly, Guild argued that the registrant and Guild have coexisted in business for over 40 years and operated in the same geographic market without any evidence of actual confusion.
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