The Ninth Circuit’s 1979 decision in AMF Inc. v. Sleekcraft Boats set out the eight likelihood of confusion factors courts in that circuit still use to decide trademark infringement claims: strength of the mark, proximity of the goods, similarity of the marks, evidence of actual confusion, marketing channels used, degree of consumer care, the defendant’s intent, and the likelihood of product line expansion. The dispute arose between AMF Incorporated, which sold high-end fiberglass boats under the Slickcraft brand, and Bruce Nescher’s smaller company selling similar watercraft as Sleekcraft.1Justia. AMF Inc. v. Sleekcraft Boats
The Eight Sleekcraft Factors
The factors work as a balancing test. No single one decides the case; a court weighs them together to judge whether a reasonably prudent buyer would likely be confused about who made the goods.2Ninth Circuit Model Civil Jury Instructions. Ninth Circuit Model Civil Jury Instructions – Section: 15.18
- Strength of the mark. How distinctive the name is and how well the public recognizes it.
- Proximity of the goods. Whether the parties sell the same, related, or complementary products.
- Similarity of the marks. How the names compare in appearance, sound, and meaning.
- Actual confusion. Evidence that real buyers were confused strongly supports a likelihood finding, though it is not required.
- Marketing channels. Whether the products are sold in similar stores or advertised through similar media.
- Degree of consumer care. How careful a buyer is expected to be given the price of the goods and the sophistication of the market.
- Defendant’s intent. Whether the mark was chosen to benefit from a competitor’s reputation.
- Likelihood of expansion. Whether either party is likely to move into the other’s market.2Ninth Circuit Model Civil Jury Instructions. Ninth Circuit Model Civil Jury Instructions – Section: 15.183Ninth Circuit Model Civil Jury Instructions. Ninth Circuit Model Civil Jury Instructions – Section: 15.19
How Proximity of the Goods Works
When two parties use similar marks on the same, related, or complementary goods, the chance that consumers will misidentify the source rises. This is the proximity piece of the analysis, and it does a lot of the work in cases where the products sit close together on a shelf or in a showroom.2Ninth Circuit Model Civil Jury Instructions. Ninth Circuit Model Civil Jury Instructions – Section: 15.18
How Buyer Sophistication Cuts the Other Way
The more expensive the product and the more sophisticated the typical buyer, the more care that buyer is expected to exercise. A discerning purchaser who researches a large purchase is less likely to be tricked by two similar names, so this factor can weigh against a finding of confusion even when the marks look and sound alike.2Ninth Circuit Model Civil Jury Instructions. Ninth Circuit Model Civil Jury Instructions – Section: 15.18
How the Court Applied the Factors
Weighing the factors together, the Ninth Circuit found that Sleekcraft infringed the Slickcraft mark. The court reversed the lower court and sent the case back with instructions to enter a limited injunction addressing the conflict between the two boat brands.1Justia. AMF Inc. v. Sleekcraft Boats