Plaintiff Dorr-Oliver, Inc. (“Dorr-Oliver”) filed suit in district court, claiming that defendants Fluid-Quip, Inc. (“Fluid-Quip”), and its president and majority stockholder, Andrew Franko, copied the trade dress of an industrial machine sold by Dorr-Oliver, in violation of the Lanham Act, 15 U.S.C. § 1051, et seq., and various state law provisions. After a bench trial, the district court ruled that Dorr-Oliver had established the infringement of its trade dress. Consequently, the court enjoined Fluid-Quip from selling its infringing product and awarded Dorr-Oliver monetary relief representing Fluid-Quip’s profits from sales of the infringing machine. The defendants appeal the district court’s decision on a number of grounds. We hold that Dorr-Oliver failed to establish a likelihood of consumer confusion and therefore reverse the judgment of the district court.
I.
The dispute in the current case requires us to take a sojourn into the field of the corn wet milling industry. Corn wet milling plants process corn by separating the four elements of the corn kernel — germ, fiber, starch, and protein. The separated elements are then sold and used to make food products, such as corn oil and corn starch. In the 1950’s Dorr-Oliver invented a new method for separating starch from protein through the use of centrifugal force. This “starch washing” process employs a series of machines, known as “starch washers,” to accomplish the goal of separation. The mixture of starch and protein is pumped through the starch washers under high pressure and is distributed through hundreds of small, stationary, tapered, plastic tubes called “cyclo- *378 nettes.” Centrifugal force is created in the cyclonettes, causing the starch and protein to exit through opposite ends of the cyclonettes and into separate outlet ports of the starch washer.
Dorr-Oliver manufactures and sells different kinds of starch washers, which vary in their outward appearance. Dorr-Oliver’s claim of trade dress infringement is based on the external design of one type of starch washer, known as the “DorrClone Type C” or the “clamshell.” The clamshell was developed and introduced by Dorr-Oliver in the late 1950’s under its registered “DorrClone” trademark. The clamshell housing is made of east steel and, in the words of the district court, resembles a forty-inch diameter bagel with a cylindrical core plugged into its center. 1 Various pipes protrude from the “bagel,” which is supported vertically above the ground by two legs. 2 Each clamshell sold by Dorr-Oliver has a nameplate displaying the “Dorr-Oliver” name, the DorrClone trademark, and the numbers of several expired patents relating to the machine. The name “Dorr-Oliver” is also cast into both sides of the clamshell’s outer housing. The other Dorr-Oliver starch washer models bear no resemblance to the clamshell.
The market for clamshell starch washers is very limited. In the United States, there are only twelve purchasers of clamshells for twenty-seven corn wet milling plants. All twelve businesses in the clamshell-purchas-ing market own and operate Dorr-Oliver clamshells. The clamshells need only be purchased once because their steel outer-housings last indefinitely. The plastic cyclonettes contained in the clamshells, however, periodically need to be replaced. In 1989 Fluid-Quip began selling replacement parts for various kinds of equipment used in the corn wet milling industry. Yet for many years, long after its patents on the clamshell had expired, Dorr-Oliver remained the sole producer and supplier of the clamshell. Dorr-Oli-ver’s customers apparently tired of paying monopoly prices for the clamshells. In 1991, Fluid-Quip was approached by several of Dorr-Oliver’s customers, who asked whether Fluid-Quip could produce and supply clam-shells at a more reasonable price. The customers desired that Fluid-Quip’s clamshells be completely interchangeable with those of Dorr-Oliver. 3 Consequently, they provided Fluid-Quip with access to the Dorr-Oliver clamshells located at their plants. Fluid-Quip measured the Dorr-Oliver clamshells and, in August of 1991, marketed its own clamshell with the precise dimensions of Dorr-Oliver’s machine. The interior of Fluid-Quip’s clamshell is identical to Dorr-Oliver’s and utilizes the same starch washing process. Moreover, although there are minor differences in the outer housings of the two manufacturer’s clamshells, the district court found, and we agree, that the general external appearance of the two clamshells is practically identical. The Fluid-Quip name, however, is east into all seven removable sections of the clamshell’s outer housing and also appears on a nameplate attached to the housing.
At the time Fluid-Quip entered the market, Dorr-Oliver clamshells sold for about $40,000, while Fluid-Quip charged approximately half that amount. Oftentimes in the industry, customers purchase several clam-shells at once, spending hundreds of thousands of dollars. The evidence at trial showed that the twelve companies in the market are very careful when making purchasing decisions regarding clamshells. In *379 the typical clamshell sales process, the supplier initially provides the customer with a preliminary bid. Before deals are closed the supplier usually engages in extensive discussions and negotiations with the customer’s upper-level management and engineers, which can last months or even years. In all of its discussions and negotiations, Fluid-Quip clearly informed its potential customers that it was not associated in any way with Dorr-Oliver. Thus, rather than misrepresenting the source of its product, Fluid-Quip truthfully held itself out as an alternative source of clamshells.
Companies in the corn wet milling industry commonly conduct tours of their plants in which people can view clamshells and other equipment involved in the milling process. Often plant managers and engineers participate in reciprocal tours of each other’s plants. Additionally, tours have been given at these plants for various international companies in the corn wet milling industry. Representatives of foreign companies also have visited Dorr-Oliver’s headquarters, and Dorr-Oliver has led tours of plants for these representatives. No evidence was offered at trial, however, showing that any of these foreign companies have ever purchased a clamshell from either Dorr-Oliver or Fluid-Quip.
Dorr-Oliver filed suit against Fluid-Quip, asserting that, under the Lanham Act and state law, 4 it had exclusive rights in the design of the clamshell’s outer housing and the use of the word “clamshell” in connection with starch washers. After a six-day bench trial, the district court concluded that Dorr-Oliver had no trademark rights in the word “clamshell.” On the other hand, the court determined that Dorr-Oliver did have a pro-tectable trade dress in the outer design of the clamshell, which Fluid-Quip had infringed. The court therefore ruled in favor of Dorr-Oliver on its Lanham Act claim and enjoined Fluid-Quip from selling its clam-shell starch washers. 5 At the time the injunction was entered, Fluid-Quip had sold eighty-one clamshells, all to customers who owned and operated Dorr-Oliver clamshells. On appeal, Fluid-Quip argues that the evidence presented at trial was insufficient to establish Dorr-Oliver’s claim of trade dress infringement.
II.
Section 43(a) of the Lanham Act provides that
Any person who, on or in connection with any goods or services, ... uses in commerce any word, term, name, symbol, or device, or any combination thereof, or any false designation of origin ... which is likely to cause confusion, or to cause mistake, or to deceive as to the affiliation ... of such person with another person, or as to the origin, sponsorship, or approval of his or her goods, ... shall be liable in a civil action by any person who believes that he or she is likely to be damaged by such act.
15 U.S.C. § 1125(a)(1). Dorr-Oliver seeks protection in the trade dress of its clamshell, which we have defined as “a product’s overall image, including its size, shape, color, graphics, packaging, and label.”
Abbott Labs. v. Mead Johnson & Co.,
Although Fluid-Quip presents a number of compelling arguments for reversal, the only one we need discuss is that the district court erred in finding that DorrOliver had demonstrated a likelihood of consumer confusion.
6
The trial court’s ultimate determination regarding likelihood of confusion is a finding of fact, which we review for clear error.
See, e.g., Forum Corp. of North Am. v. Forum, Ltd.,
The requirement of consumer confusion is vital to protecting the basic policies behind federal trademark law. As explained by the Supreme Court,
[ t]he Lanham Act provides national protection of trademarks in order to secure to the owner of the mark the goodwill of his business and to protect the ability of consumers to distinguish among competing producers. National protection of trademarks is desirable, Congress concluded, because trademarks foster competition and the maintenance of quality by securing to the producer the benefits of good reputation.
Park ’N Fly, Inc. v. Dollar Park & Fly,
Dorr-Oliver argues that Fluid-Quip attempted to capitalize on Dorr-Oliver’s goodwill by confusing consumers into thinking that Fluid-Quip’s clamshells were made by, or in some way connected with, DorrOliver. In evaluating the likelihood of consumer confusion for this claim of trade dress infringement, the factors to be considered include: (1) the similarity of the trade dresses; (2) the products to which the trade dresses are attached; (3) the area and manner of concurrent use; (4) the degree of care likely to be exercised by consumers; (5) the strength of the plaintiffs trade dress; (6) actual confusion; and (7) intent of the defendant to pass off its products as those of the plaintiff.
See, e.g., Badger Meter,
The district court found that there was “no possibility of confusion by the purchaser at or near the point of sale.”
Although this analysis at first blush appears to foreclose any finding that consumers are likely to be confused, the district court held that the Lanham Act applies not only to point-of-sale confusion, but also to “post-sale confusion” of potential purchasers. In support of its holding, the district court relied on
Lois Sportswear, U.S.A., Inc. v. Levi Strauss & Co.,
[ P]ost-sale confusion as to source is actionable under the Lanham Act.... In the instant case, this postsale confusion would involve consumers seeing [defendants’] jeans outside of the retail store, perhaps being worn by a passer-by. The confusion the Act seeks to prevent in this context is that a consumer seeing the familiar stitch *382 ing pattern will associate the jeans with [Levi Strauss] and that association will influence his buying decisions. Clearly, in this post-sale context [defendants’] labels, most of which having been long since discarded, will be of no help.
Id.
at 872-73 (emphasis added). Thus, while actual purchasers might have ultimately been informed regarding the source of the defendants’ jeans, the court found that the similarity in the stitching patterns would cause prospective purchasers to seek out the defendants’ jeans thinking that they were associated with Levi Strauss.
Id.
at 873. The visibility of the pocket stitching to the consuming public effectively advertised an association of the defendants’ jeans with Levi Strauss. After applying its multifactor confusion test and considering the evidence supporting Levi Strauss’ claim, the court concluded that there was a likelihood of consumer confusion.
Id.
at 876.
See also Levi Strauss & Co. v. Blue Bell, Inc.,
Dorr-Oliver correctly notes that the basic principles expressed in
Lois Sportswear
can be found within our own precedent. For instance, we have stated that in evaluating the likelihood of consumer confusion, courts should consider “the group of potential purchasers of both products.”
Forum Corp.,
The district court found that there was a likelihood of post-sale confusion because various people, including potential foreign purchasers, “would be unable to distinguish Fluid-Quip’s clamshells from Dorr-Oliver’s when viewing a starch washing line” during tours of industry plants.
In our judgment, the evidence relied on by Dorr-Oliver and the district court is not sufficient to establish a likelihood of consumer confusion. The proper examination is not whether some people viewing clamshells in industry plants might be confused, but rather whether
consumers
in the market for clamshells are likely to be confused. Indeed, the Lanham Act is concerned with “customer confusion when choosing to purchase, or not purchase, the items, not public confusion at viewing them from afar.”
Nike,
Moreover, we would not reach a different result even if we agreed with Dorr-Oliver’s position that viewers of operating clamshells are potential clamshell purchasers and should be factored into the likelihood of confusion calculus. Dorr-Oliver’s only theory of confusion is that these potential purchasers, upon seeing the two manufacturers’ names on the clamshells, will likely believe that Fluid-Quip’s clamshells are affiliated with Dorr-Oliver. According to Dorr-Oliver, this will confuse the potential purchasers into having an “initial interest” in Fluid-Quip’s product. Yet we fail to see why people viewing two substantially identical clamshells would leap to this conclusion. We believe that, in the context of this industrial machine, the typical consumer will not assume that the two manufacturers are associated in some way. Rather, where product configurations are at issue, consumers are generally more likely to think that a competitor has entered the market with a similar product.
See Versa,
Ultimately, rather than being grounded in a plausible theory of consumer confusion, the district court’s opinion appears to be based on its general notion that “[i]t is inherently unfair for a competitor to enter the market on the back of the originator of a design.”
In the current case Dorr-Oliver reaped the rewards of its patents on the clamshell for seventeen years, after which time the product passed into the public domain. Fluid-Quip then entered the clamshell market with a product virtually identical in appearance
*384
and represented itself to potential customers as a competitor of Dorr-Oliver. This is certainly competition, but the similarity of the two clamshells, standing alone, does not make it unfair. Indeed, the “mere inability of the public to tell two identical articles apart is not enough to support an injunction against copying or an award of damages for copying that which the federal patent laws permit to be copied.”
Stiffel,
III.
We have held that “a finding of likely confusion can no more be based on pure conjecture or a fetching narrative alone than any other finding on an issue on which the proponent bears the burden of proof.”
See Libman,
Notes
. The clamshell actually comes in two sizes. The forty-inch diameter model is the larger size.
. The appearance of the clamshell starch washer is somewhat difficult to describe. The curious reader can find a drawing of Dorr-Oliver's clam-shell in an appendix to the district court's opinion.
See Dorr-Oliver, Inc. v. Fluid-Quip, Inc.,
. The cyclonettes inside the clamshell must be replaced approximately every two years. The general practice in the industry is to disassemble an entire bank of clamshells and replace the cyclonettes in each machine. When the clam-shells are then reassembled, parts from one unit are sometimes switched with parts from another unit. Since the businesses that were interested in Fluid-Quip's production of clamshells already had Dorr-Oliver machines, the companies indicated to Fluid-Quip their desire for clamshells that were similar in appearance to, and had parts interchangeable with, Dorr-Oliver units.
. Dorr-Oliver brought claims under the common law of unfair competition, the Illinois Deceptive Trade Practice Act, 815 ILCS 510, the Illinois Consumer Fraud and Deceptive Business Practices Act, 815 ILCS 505, and the Illinois Counterfeit Trademark Act, 765 ILCS 1040.
. The district court also ruled in favor of Dorr-Oliver on three of its four state law claims. The court concluded that its finding of trade dress infringement under the Lanham Act was sufficient to demonstrate that Dorr-Oliver engaged in unfair competition and violated the Illinois Deceptive Trade Practices Act and the Illinois Consumer Fraud Statute. The court, however, found that Dorr-Oliver failed to prove a necessary element of its claim under the Illinois Counterfeit Trademark Statute-that Fluid-Quip had intended to deceive consumers.
. We do wish to make one point regarding the district court's finding of inherent distinctiveness. In making this finding, the district court relied on our statement in
Computer Care
that a "trade dress is inherently distinctive if it is ‘sufficiently distinctive to allow consumers to identify the product from the trade dress.' "
. This conclusion is strongly supported by the fact that the only actual sales of Fluid-Quip clamshells were made to companies in the industry who also owned and operated Dorr-Oliver clamshells. Fluid-Quip introduced its clamshell at the behest of some of these companies, who evidently sought a lower-priced alternative to Dorr-Oliver’s clamshell. The companies, who had previously dealt with Dorr-Oliver, undoubtedly knew that they were dealing with Fluid-Quip and not Dorr-Oliver.
. Perhaps the error below is best illustrated by the district court's belief that the interchangeability of clamshell parts supported Dorr-Oliver's claim of trade dress infringement. The district court reasoned that consumers would be confused by a Dorr-Oliver outer housing on a Fluid-Quip core and incorrectly attribute any mechanical difficulties to Dorr-Oliver. Yet this so-called "confusion" would exist regardless of the external appearance of Fluid-Quip's clamshell. The patent laws proscribe the creation of a monopoly on the clamshell's internal parts in this manner.
