In Application of E. I. DuPont DeNemours & Co., 476 F.2d 1357, 177 USPQ 563 (CCPA 1973), a case involving an appeal from the Trademark Trial and Appeal Board, one of our predecessor courts listed thirteen factors that are relevant in a likelihood of confusion analysis. See id. at 1361, 177 USPQ at 567. The thirteen factors are: (1) the similarity or dissimilarity of the marks in their entireties as to appearance, sound, connotation and commercial impression; (2) the similarity or dissimilarity and nature of the goods or services as described in an application or registration or in connection with which a prior mark is in use; (3) the similarity or dissimilarity of established, likely-to-continue trade channels; (4) the conditions under which and buyers to whom sales are made, i.e., "impulse" vs. careful, sophisticated purchasing; (5) the fame of the prior mark (sales, advertising, length of use); (6) the number and nature of similar marks in use on similar goods; (7) the nature and extent of any actual confusion; (8) the length of time during and conditions under which there has been concurrent use without evidence of actual confusion; (9) the variety of goods on which a mark is or is not used (house mark, "family" mark, product mark); (10) the market interface between applicant and the owner of a prior mark; (11) the extent to which applicant has a right to exclude others from use of its mark on its goods; (12) the extent of potential confusion, i.e., whether de minimis or substantial; (13) any other established fact probative of the effect of use. See id.