A trademark demand letter can feel like the natural first move when another seller, listing, or storefront starts using branding that looks a little too close to yours. But in many brand disputes, the real leverage comes before the letter goes out. It comes from the quality of the marketplace evidence behind it.
That matters because trademark disputes often turn on facts from the real world: how the mark appears, where the goods are sold, how they are described, whether the products travel in similar channels of trade, and whether customers could plausibly think the products come from the same source. The USPTO explains that likelihood of confusion commonly depends not just on similarity between marks, but also on whether the goods or services are related and move through similar trade channels. The USPTO also notes that the amount and quality of evidence can significantly affect the outcome of an infringement dispute.
In this post you’ll learn how to gather marketplace evidence in a way that is organized, practical, and more useful to an attorney reviewing a possible brand conflict. If you want a broader primer on the legal framework behind brand disputes, this overview of how trademark conflicts are usually analyzed and enforced can help set the stage.
<aside> 💡 Scroll to the bottom for every post in this series.
</aside>
A demand letter without evidence can read like opinion. A demand letter backed by marketplace proof often reads more like a documented record.
That distinction matters for a few reasons:
First, trademark analysis is heavily fact-specific. The USPTO’s likelihood-of-confusion guidance focuses on how consumers encounter marks in the marketplace, including similarities in sound, appearance, meaning, and overall commercial impression, along with the relatedness of the goods or services.
Second, online evidence can disappear fast. Product titles get edited. Seller names change. Listings go dark. Images are swapped. Reviews are removed. Sponsored placements rotate. In fast-moving e-commerce environments, a brand owner may be looking at one version of the listing today and a different version next week.
Third, some online evidence is stronger than other online evidence. The USPTO’s specimen guidance describes specimens as real-life evidence of how a mark is actually used in commerce. That idea is useful beyond registration practice: when evaluating a possible infringement issue, real marketplace use tends to matter more than unsupported claims about use.
Before gathering screenshots, it helps to define the issue in plain language. In many cases, the question is not simply, “Are they using my name?” It is closer to one of these:
This step keeps the evidence collection process focused. If the suspected problem is keyword baiting in a marketplace listing, the evidence set may look different than a counterfeit dispute, a private-label conflict, or a storefront impersonation issue.