Everyone wants a number here. There is not one. But the test is more predictable than it looks, and knowing how it is actually applied will tell you fairly quickly whether your near miss is a problem.
Three dimensions, and any one can be enough
Marks are compared for sound, appearance and meaning, and for the overall commercial impression those produce. Similarity in a single dimension can be enough on its own.
- Sound. Spelling is nearly irrelevant if the marks are said the same way. There is no correct pronunciation of an invented word, so the comparison assumes the pronunciation that makes them closest.
- Appearance. How the marks look on a shelf or in a results list. Shared prefixes matter more than shared endings, because that is where the eye starts.
- Meaning. Two marks with no letters in common can still collide if they mean the same thing. This is where translations bite, under the doctrine of foreign equivalents.
As a whole, but with a dominant part
Marks are compared in their entireties, and you cannot defend a conflict by pulling a mark apart and arguing the pieces are different. That said, within a composite mark some matter more than others. A descriptive or generic word carries little weight, so if your mark is that word plus a genuinely distinctive term, the distinctive term is where the comparison lands.
The practical result is one people find unfair: adding a word usually makes it worse. If a registered mark is SUMMIT for backpacks, calling yours SUMMIT GEAR does not create distance. It looks like a product line from the same owner.
Imperfect recollection
The comparison is not side by side. It imagines someone who encountered one mark weeks ago and now meets the other, working from memory. Distinctions that are plain when the marks sit together often carry no weight at all, because nobody in the real world sees them together.
What actually creates room
Three things reliably matter.
The strength of the shared element. If the shared word is weak, or is already used by many owners in the field, buyers have learned to tell those marks apart by their small differences, and small differences start counting. A crowded field narrows everyone’s scope, including the earlier owner. See can you trademark a common word.
What you add, and where. Adding a distinctive word to a weak shared term can genuinely separate two marks. Adding a descriptive one to a strong term does not.
How related the goods are. Similarity is only half the test. Two moderately similar marks on unrelated goods often coexist; the same pair on competing goods does not. See the different-industry question.
Adding a word rarely saves you
The most common instinct when a name is close is to add something to it, and it is the one that works least often. If the added word describes what you sell, an examiner discounts it, because a descriptive word cannot distinguish two brands from each other. SUMMIT and SUMMIT COFFEE are not meaningfully different marks to somebody buying coffee.
What matters is which part is doing the identifying. If the shared element is the distinctive part and your addition is the ordinary part, you have not moved. If the shared element is weak and your addition is the striking one, you may have.
Where the shared word is weak to begin with
The reverse case is worth knowing because it is the one that gets people out of trouble. When a word is descriptive, laudatory or simply crowded, it gets thin protection, and small differences count for more. Dozens of live registrations containing the same ordinary word tell an examiner that buyers are already distinguishing between them by the other elements.
This is the crowded field, and it is why common words behave differently from coined ones. A crowded term does not make your name safe. It narrows what the other owners can complain about.
What actually creates distance
Distance comes from changing what the mark is, not from decorating it:
- A different first syllable. Beginnings carry disproportionate weight in both reading and recall, so changing the start moves a mark further than changing the end.
- A different meaning. Two marks that sound somewhat alike but evoke genuinely different things are easier to separate than two that share a concept.
- A different number of syllables and a different rhythm, which changes how the name sounds said aloud rather than how it looks typed.
- Dropping the shared element entirely, which is the only move that reliably works when the shared part is the distinctive one.
Changing a letter while keeping the sound is not distance. Neither is a different font, since a standard-character registration covers the words however they are styled.
A rough triage
- Same sound, related goods. Treat as a conflict regardless of spelling.
- Your mark contains their distinctive term. Treat as a conflict until something specific says otherwise.
- Shared term is weak or crowded, and you added something distinctive. Worth a closer look; this is the space where marks coexist.
- Similar only in a descriptive element. Usually survivable, because nobody owns the descriptive part.
None of that is a substitute for advice on your specific facts. It is the frame examiners and the Board use, which is enough to tell you whether you are arguing about the interesting question or the settled one.