A conceptually strong trademark is a distinctive trademark. A conceptually weak trademark, however, is entitled to a comparatively narrow scope of protection. When confronted with a Section 2(d) refusal for likelihood of confusion with a registered mark, one strategy is to present evidence of third-party registrations of similar marks for similar goods or services. See Jack Wolfskin Ausrustung Fur Draussen GmbH & Co. KGAA v. New Millennium Sports, S.L.U., 797 F.3d 1363, 116 USPQ2d 1129, 1136 (Fed. Cir. 2015) (“[E]vidence of thirdparty registrations is relevant to ‘show the sense in which a mark is used in ordinary parlance,' … that is, some segment that is common to both parties' marks may have ‘a normally understood and well-recognized descriptive or suggestive meaning, leading to the conclusion that that segment is relatively weak'” (quoting Juice Generation, Inc. v. GS Enters. LLC, 794 F.3d 1334, 115 USPQ2d 1671, 1674 (Fed. Cir. 2015))); see also Tao Licensing, LLC v. Bender Consulting Ltd., 125 USPQ2d 1043, 1057 (TTAB 2017) (“third-party registration evidence that does not equate to proof of third-party use may bear on conceptual weakness if a term is commonly registered for similar goods or services” (citing Tektronix, Inc. v. Daktronics, Inc., 534 F.2d 915, 189 USPQ 693, 694-95 (CCPA 1976))). “[E]xtensive evidence of third-party use and registrations is ‘powerful on its face,' even where the specific extent and impact of the usage has not been established.” Jack Wolfskin, 116 USPQ2d at 1136 (citing Juice Generation, 115 USPQ2d at 1674). (emphasis added).

“The weaker [the registrant's] mark, the closer an applicant's mark can come without causing a likelihood of confusion and thereby invading what amounts to its comparatively narrower range of protection.” Juice Generation, Inc. v. GS Enters. LLC, 794 F.3d 1334, 115 USPQ2d 1671, 1676 (Fed. Cir. 2015) (internal citations omitted). See also Palm Bay Imps., Inc. v. Veuve Clicquot Ponsardin Maison Fondee En 1772, 369 F.3d 1369, 73 USPQ2d 1689, 1693 (Fed. Cir. 2005) (“Evidence of third-party use of similar marks on similar goods is relevant to show that a mark is relatively weak and entitled to only a narrow scope of protection.”). 

If there is evidence a mark, or an element of a mark, is commonly adopted by many different registrants, that may indicate the common element has some non-source identifying significance that undermines its conceptual strength as an indicator of a single source. Spireon, Inc. v. Flex Ltd., 71 F.4th 1355, 1364, 2023 USPQ2d 737, at *5-6 (Fed. Cir. 2023). 

This relates to the sixth DuPont factor, namely, the number and nature of similar marks in use for similar goods or services. 

The TTAB recently reversed a Section 2(d) refusal of the SUN CHLORELLA mark for “Udon noodles made in whole or significant part of chlorella” (with CHLORELLA disclaimed) in view the registered SUN NOODLE mark for “noodles.” The TTAB noted that the distinctive component of the marks was the term SUN (or the foreign equivalent thereof); and that, whether as an English language term or a term in an Asian language translated to “successful” or “rich,” the term "SUN" retains a positive connotation suggesting prosperity or a beneficial outcome. 

In response to the refusal, the applicant had submitted evidence of sixteen third-party, use-based registrations for mark containing the word SUN for noodles, and eighteen other SUN marks for other food-related goods. 

[E]vidence of extensive registration by third parties of “SUN” formative marks for goods identical or related to those identified in the cited registration demonstrates that the cited mark is conceptually weak to such an extent that it is entitled to a very narrow scope of protection.

Although the TTAB had found that the marks were more similar than dissimilar and the channels of trade and classes of consumers overlapped, the TTAB concluded that confusion was unlikely.