Di-Stink–tive Trade Dress: Play-Doh Registers Its Scent with the USPTO

By Samuel Meredith

On May 18, 2018, Hasbro announced that the United States Patent and Trademark Office (“USPTO”) approved its application to register the scent of its well-known Play-Doh clay. 1 Barring a successful legal challenge to the registration, this development means that Hasbro will be able to prevent its competitors from using confusingly similar scents for their products.2 Although the number of registered scents has grown, they are still relatively obscure.3 For this reason, the registration of Play-Doh’s scent with the USPTO may be puzzling to lawyers and non-lawyers alike. Indeed, the news of Hasbro’s successful registration likely prompted questions such as “Should scents be allowed to have trademark protection?” and “How does one determine whether a scent is worthy of trademark protection?”


Trademark law obviously does protect scents under some circumstances, as the USPTO has considered them registerable since 1990. 4 But should that be the case?

The answer to this question is somewhat complicated and has been the subject of a philosophical, economic, and practical debate.5

A. Can Scents Really Work as Trademarks?

From a philosophical standpoint, there has been disagreement among commentators as to whether fragrances can really be effective as trademarks. The close connection between our sense of smell and our memories seems to indicate that fragrances can be useful tools for accomplishing the main goal of every trademark—source identification.6 Nevertheless, some have questioned the ability of fragrances to achieve this goal, arguing that “when it comes to recalling a particular smell itself or remembering its name, there is ample scientific support for the conclusion that the sense-memory link is far weaker [in the case of the olfactory sense] than in the case of sound and sight.”7

Even so, one can envision how a product’s scent could play an important role in “post-sale” source identification.8 Imagine, for example, a sculpting clay similar to Play-Doh. In order to use such a product, consumers have to remove it from its container, thereby isolating it from its more traditional source indicators, such as its logo and word mark. If you were to see the product in such a state (perhaps as part of a display at a school art exhibit),9 you might be incapable of ascertaining its source. Play-Doh, on the other hand, thanks to its distinctive aroma, could still be identified under these circumstances. Thus, scents do have the potential to be effective source identifiers.

Scents, however, are not always used purely for source identification. Indeed, fragrances often serve an aesthetic function.10 This highlights another point of disagreement about the protection of so-called “fragrance marks”11—that is, can trademark law really protect scents when it does not provide protection for product features that merely possess “aesthetic functionality”?12 Some have argued that “the aesthetic functionality doctrine effectively precludes serious consideration of granting scents trademark protection” because adding a welcoming aroma to a product will always serve the aesthetic functions of “attracting” and “pleasing” consumers.13

On the other hand, given the protected status of other arguably aesthetic product traits, it would seem arbitrary to disallow trademark protection for scents on aesthetic functionality grounds. For example, courts have not hesitated to award trademark protection to single colors, the aesthetic functionality doctrine notwithstanding.14 If courts are willing to protect single colors, which arguably always serve some aesthetic function (they would never be used if they did not make the product “pop” at least a little bit), then why should they be hesitant in the case of fragrances?15 Besides, “[t]he ultimate test of aesthetic functionality . . . is whether the recognition of trademark rights would significantly hinder competition;”16 and, as the following discussion demonstrates, the protection of fragrances would not necessarily be an impediment to competition

B. Is Giving Trademark Protection to Fragrances Unfair to Competitors?

From an economic standpoint, the debate over fragrance marks highlights the classic dilemma that underlies all intellectual property law: finding the proper balance between avoiding unfair monopolies and encouraging innovation by preventing free-riding.17 Those who are more concerned about the former argue that giving scents trademark protection will cause “scent depletion,” which will, in turn, stifle competition due to the “finite number” of marketable fragrances.18

This concern, however, is likely overstated. Indeed, courts have already disposed of this issue in the context of colors.19 One might argue that scents are distinguishable from colors because there are fewer choices as far scents are concerned,20 but the hand-wringing about scent depletion still seems misplaced in light of the functionality doctrine.21 Indeed, the functionality doctrine likely provides a sufficient backstop against scent depletion in industries where it may be a legitimate concern. Depletion could, for example, be a real issue for purveyors of home care and personal hygiene products.22 In these product categories, however, scent is inextricably connected to “the quality of the [product],” thus making it functional and incapable of trademark protection.23 Thus, the recognition of fragrance marks does not necessarily foster an anticompetitive landscape.

C. How are Courts to Go About Enforcing the Rights Associated with Fragrance Marks?

The debate over fragrance marks has more practical underpinnings as well. For example, some scholars have noted that it may be challenging for courts to reliably enforce trademark rights in cases involving protected scents.24 Specifically, commentators have argued that awarding scents trademark protection could lead to “scent confusion” for courts.25 This is yet another argument that has been disposed of in the realm of colors.26 Nevertheless, some commentators still assert that scent confusion is a legitimate risk because it is “impossible” to formulate “reliable descriptions of scents” and challenging “to distinguish similar scents from each other.”27 These concerns are not likely to be persuasive in court given the self-confidence that judges often have when approaching tough analytical questions such as this one.28 Furthermore, because the Lanham Act uses “the broadest terms” to describe the subject matter of trademarks, 29 it appears likely that judges will be willing to award protection to fragrance marks in spite of the administrative difficulties that doing so may present


Thus, it seems likely that fragrance marks are here to stay. In light of this new knowledge you may find yourself wondering whether you should add a fun, unique scent to your product. However, before you start experimenting with different blends of eucalyptus and forest berries, there are a few things you should know about the realities of applying to register a fragrance mark.

First, you should bear in mind that not all scents will be protectable. As explained above, the aesthetic functionality doctrine likely makes trademark protection impossible in industries where there is a correlation between product scent and product quality.30 Thus, before you begin devoting resources to a fragrance mark application, you should consider whether your product belongs to a scent-centric product category

Secondly, even conclusive evidence of nonfunctionality cannot render a scent protectable on its own. One also needs “[a] ‘substantial showing of acquired distinctiveness'” to prove that a fragrance is worthy of trademark protection.31 With traditional marks, one can often satisfy this requirement by presenting evidence of five years’ worth of “substantially exclusive and continuous use.”32 When the would-be trademark is a scent, however, additional evidence (such as consumer survey evidence or proof of scent-focused marketing campaigns) will probably be required to establish acquired distinctiveness33

Finally because there are USPTO fees and legal costs associated with pursuing a trademark registration, businesses should carefully balance potential risks and rewards before attempting to register a fragrance mark.


Although protecting fragrance marks may seem like a questionable proposition, Play-Doh’s recent success indicates that the USPTO continues to be open to the idea. Even so, obtaining a registered fragrance mark presents legal and practical obstacles that businesses should take into account before attempting to establish a scent of their own. Otherwise, they may end up devoting substantial time and resources to a failed trademark application—and that would stink.