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Infringement & Likelihood of Confusion


Imputed Knowledge
In certain circumstances, the law treats a person as having known about something, even if that person didn’t actually have such knowledge. Attributing knowledge in this way is often due to a sense that the person should have known and would have known, if she had taken even a slight interest in finding out.

Prima Facie:
Literally “on its face” in Latin, prima facie evidence is evidence which, in itself, is sufficient to prove a fact unless evidence to the contrary is provided.

Assuming we have a valid registered mark, §1114 gives us the basics of trademark infringement. This section essentially prohibits the use of reproductions, counterfeits, copies, or imitations of a registered mark, when

“such use is likely to cause confusion, or to cause mistake, or to deceive.”

The infringer need not be actually aware of the registered mark; registration imputes knowledge of the mark’s existence on all second-comers (this is one of the reasons to always register marks, if possible). The mark doesn’t have to be used on the same goods and or/services, and the mark could have been independently created (i.e., not physically copied). (Note that §1125(a) contains similar provisions for unregistered marks, not discussed here.)

The major question here, in theory and in practice, is how to determine whether or not a mark is likely to cause confusion. One leading case on this issue is Polaroid Corp. v. Polarad Electronics Corp., 287 F.2d 492, 495 (2d Cir. 1961), where the court provided 8 factors to consider:

  1. the strength of the mark.
  2. the degree of similarity between the two marks.
  3. the proximity of the products/services.
  4. the likelihood that the prior owner will bridge the gap.
  5. actual confusion.
  6. the defendant's good faith in adopting its own mark.
  7. the quality of the defendant's product.
  8. the sophistication of the buyers.

While Polaroid is not binding on other circuits, the other Circuit Courts have enunciated their own lists of factors, as summarized in Ginsburg et. al at 428 (e.g., “Roto-Rooter” factors in the Fifth Circuit, see Roto-Rooter Corp. v. O'Neal, 513 F.2d 44, 46 (5th Cir. 1975), “Beer Nuts” factors in the Tenth, see Beer Nuts, Inc. v. Clover Club Foods Co., 805 F.2d 920, 928 (10th Cir. 1986)). Further, the factors mentioned by these courts are not necessarily exhaustive. That said, the first three factors are often considered to be the most important.

EXAMPLE: “Friggin’ Chicken” is a chain of fast-food restaurants known nationwide for its “Friggin’ Fries.” By using the fanciful word “Friggin'” before each of their menu items, the company has established a link in the public mind between that term and their restaurants. In 1985, the various Friggin’ menu item names, along with the restaurant name, are placed on the primary register by the company’s corporate counsel. All technical requirements, including affidavit of use and renewals are regularly met. In 1997, a Tennessee retiree decides to market one of his favorite fly-fishing lures. Because the lure is so difficult to make, (hence the high price he decides to charge,) he has always referred to it among his friends as that “friggin’ fishin’ lure.” He decides this would be an excellent name to use on the lure’s package. Within a few months Friggin’ Chicken’s legal department becomes aware of the retiree’s lure, and files a suit for infringement of the registered mark “Friggin’ Fish Sandwich.”

How are the Polaroid factors applied here?

  1. The strength of the mark here is substantial. The company has spent years establishing the mark in the nation’s mind, and the mark is used on all the company’s products, as well as in the name of the restaurants themselves. This factor leans toward a finding of infringement.
  2. The marks here are clearly very similar. Although we have not taken into consideration the way in which the words are written (e.g., font, color, etc.), nor have we considered any logos accompanying the mark, the words “Friggin’ Fishing…” are almost identical to “Friggin’ Fish…” This factor leans toward a finding of infringement.
  3. The products/services are not very similar at all. The registered mark covers restaurant services and menu items, while the potential infringer is using the mark on sporting equipment. This factor leans away from a finding of infringement.
  4. Although the plaintiff here might decide to offer a variety of products or services unlike its current restaurant business, it is unlikely that Friggin’ Chicken would expand into the realm of sporting goods. This factor leans away from a finding of infringement.
  5. In the hypothetical we have not said anything about actual customer confusion caused as a result of the lure’s mark. This is an inherently factual question dependent on market studies and surveys.
  6. There is nothing to indicate that the retiree intended to get a “free ride” on the plaintiff’s back by using the mark. But despite this lack of bad faith, the adequacy of a defendant’s trademark search is also relevant to the question of good faith. Although likely due to the retiree’s lack of sophistication, the lack of any due diligence before embarking on this enterprise might count against the defendant here.
  7. If the lures are of a high quality, the damage to the plaintiff would be less than if the retiree makes junk. Generally, it is not good for the potential infringer if his goods are of lower quality than those of the plaintiff's.
  8. Consumer sophistication might be argued either way, and the successful party will likely be the one who provides the best study data. How sophisticated are fast-food restaurant patrons? How sophisticated are expensive fly-fishing lure purchasers? More sophisticated consumers are less likely to become confused by similar marks.

If you had to decide this case, how would you rule? Note how many of the factors are factually-dependent, and how many others could be argued either way. Also, note that the overall question of likelihood of confusion is a question of fact in some circuits but a mixed question of fact and law in others (e.g., 2d and 6th).

Cases abound within each circuit discussing the various factors, but the above hypothetical should give you a general sense for how they play out. One important thing to keep in mind is that surveys and studies can make or break an infringement suit. But it is not simply the quality of the data which is important; the type of survey/study used can make all the difference in the world.

In E. & J. Gallo Winery v. Consorzio Del Gallo Nero, 782 F. Supp. 457, 466 (D. Cal. 1991) the court noted that the value of a side-by-side comparison of the registered mark with the potential infringer might be irrelevant. Instead, the court should consider whether the defendant’s mark, standing alone, is likely to cause confusion (citing a district court case within the Second Circuit as well as decisions from the Seventh and Ninth Circuits).

“On the other hand,”
the court notes,
"the best survey might be one which attempts to most closely replicate the marketplace setting in which consumers will typically encounter the competing marks.”
Gallo at 466.

In short, parties to an infringement case must carefully research the factors used in the area and must determine how best to conduct studies and surveys to swing the factors in their direction. There is no crystal ball here, and sometimes the party with the deepest pockets wins, while at other times a sharp legal team can make up for a lack of funding (e.g., by commissioning only the type of survey the courts in that circuit like to use, rather than wasting resources on data the court is likely to ignore).

Reverse Confusion

Although not terribly common, occasionally a plaintiff sues in a case of “reverse confusion.” This takes place when a large, junior user saturates the market and their mark becomes more prominent than the senior mark. While the junior user here would clearly not be hoping to benefit from the confusion between its mark and the senior mark, the senior user can still sue as it is still damaged by the junior use. See e.g., Sands, Taylor & Wood Co. v. Quaker Oats Co., 978 F.2d 947 (7th Cir. 1992) (“Gatorade is Thirst Aid” infringes on plaintiff’s “Thirst-Aid” due to reverse confusion); W.W.W. Pharmaceutical Co. v. The Gillette Co., 984 F.2d 567 (2d Cir. 1993) (Plaintiff’s reverse confusion claim failed against “Right Guard Sport Stick,” upon application of Polaroid factors).