In the case of Hanover Star Milling Company v. Metcalf in 1915, the U.S Supreme Court ruled on a dispute involving trademark infringement and unfair competition. The plaintiff, Hanover Star Milling Company, claimed that their competitor Metcalf was using a similar name for his flour product which caused confusion among customers and resulted in loss of business for them. However, the court found no evidence to support this claim as there were significant differences between both products including packaging design and price points. Furthermore, it was established that 'Star' is a common term used by many companies within the industry making it difficult to associate with one particular brand exclusively. Therefore, they concluded that any confusion arising from similarity in names would be minimal at best due to these distinguishing factors present in each product's marketing strategy.

In the dissenting opinion for Hanover Star Milling Company v. Metcalf, it was argued that the majority's decision to allow a trademark infringement claim based on confusion between two similar trademarks could lead to an overreach of federal power and stifle competition. The dissent emphasized that while protecting consumers from deception is important, this should not be used as a pretext for creating monopolies through overly broad interpretations of trademark rights. It was also pointed out that there were significant differences between the two marks in question which would prevent reasonable consumers from being misled. Furthermore, they believed that any potential confusion should be addressed by state law rather than federal courts.