Practice Tips for Determining Likelihood of Confusion – Factors to Consider when Assessing Similarity of Trademarks

Contributed by Kristin A. Biedinger

When reviewing any new trademark application, one of the first issues an Examiner will address is whether or not there is a “likelihood of confusion” between the new mark and any other mark that is already registered with the United States Patent and Trademark Office (“USPTO”).  While likelihood of confusion is a somewhat subjective analysis, the Examiner does balance several different factors.  These factors, which were outlined in Application of E.I. DuPont Denemours & Co., 476 F. 2d 1357, 1361 (C.C.P.A. 1973), are commonly referred to as the “DuPont factors” and include:

The similarity or dissimilarity of the marks themselves with respect to sight, sound, meaning, and commercial impression;

  1. The similarity or dissimilarity and nature of the goods or services;
  2. The similarity or dissimilarity of trade channels; and
  3. The sophistication of customers.

The recent case In re St. Helena Hospital, provides some good guidance on assessing factor #1, the similarity or dissimilarity of the marks themselves.


St. Helena Hospital filed a federal application to register the service mark “TAKETEN” for its ten day residential health program.  The application described the services as “health care services, namely, evaluating weight and lifestyle health and implementing weight and lifestyle health improvement plans in a hospital-based residential program” and sought registration in class 44.

The Examiner refused registration, citing a likelihood of confusion under 15 USC §1052(d)1 with two registered marks:


  • Registration No.: 2,577,657 (“the ‘657 Registration”) for “TAKE 10!” in international class 16 for “printed manuals, posters, stickers, activity cards and educational worksheets dealing with physical activity and physical fitness”; and


  • Registration No.: 2,674,182 (“the ‘182 Registration”) for “TAKE 10!” (and design) in international class 16 for “printed manuals, posters, stickers, activity cards, and educational worksheets dealing with physical activity and physical fitness.”


In considering the DuPont factors, the Board found a likelihood of confusion and affirmed the Examiner’s refusal.  St. Helena Hospital appealed to the Federal Circuit Court of Appeals.  The Federal Circuit found the Board’s decision not supported by sufficient evidence in three out of the four DuPont Factors and reversed and remanded for further proceedings.


Despite the lack of discussion with respect to the factors not supported by sufficient evidence (factors 2-4 above), the opinion does provide some useful practice tips for assessing the similarity or dissimilarity of the marks when assessing a likelihood of confusion.





St. Helena Hospital argued three specific differences between the “TAKETEN” mark and the “TAKE 10!” registered marks: (1) that the numerical portion of the mark “TAKETEN” is spelled out as opposed to the “TAKE 10!” registered marks were the numerical portion is written as a number, (2) that there is no space between the words in “TAKETEN,” and (3) that “TAKETEN” does not include any punctuation, namely an exclamation mark.


The Federal Circuit was not persuaded. First, the Federal Circuit noted that the marks were phonetically identical even though they were spelled differently and that in this context “ten” and “10” had the same meaning.  Therefore, any differences between the marks use of “ten” versus “10” were minimal.


Second, the Federal Circuit noted that when assessing the similarity of marks, they must be considered “in light of the fallibility of memory” and not subject to a side-by-side comparison.  Again, the Federal Circuit found any differences in the appearance of the marks to be minimal.


Third, the Federal Circuit noted that there is no correct punctuation of a trademark and that consumers may pronounce it differently from the brand owner.  Therefore, St. Helena Hospital’s argument that the use of an exclamation mark in the registered marks changed the way the marks were pronounced (emphatically v. passively) was not persuasive.  Here, the use of the exclamation mark did not change the way the mark was pronounced or the connotation it conveyed.





  • In assessing likelihood of confusion, marks must be considered based on the memory of consumers and not based on a side-by-side comparison.
  • Similarity may be found where the marks are phonetically identical even if they are spelled differently.
  • There is no correct pronunciation of a trademark.
  • Punctuation of a trademark does not always change its connotation.

115 USC §1052(d) states in relevant part, “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… 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….”