How ordinary product words actually spread across the 45 trademark classes, computed from all 64,313 entries in the USPTO's own Trademark ID Manual.
Trademark classification is usually explained as though each product has a class: clothing is 25, software is 9, restaurants are 43. Measured against the USPTO's own list of accepted identifications, that is not how the words behave. Of 620 ordinary goods and services words with at least 25 accepted descriptions each, 92% appear in four or more classes and 46% have no single class holding even half of their descriptions. The median word appears in 10 classes; the widest spreads reach 40.
The reason is that a class follows the identification rather than the noun. One word names the raw material, the finished article, the accessory, the machine that makes it and the service of selling it, and those are deliberately separate classes. The word electrical is the clearest case in the data: 2,804 accepted descriptions contain it, spread across 40 of the 45 classes, and the largest single class holds only 29% of them.
Words with at least 100 accepted descriptions where the leading class holds under 45% of them.
| Word | Descriptions | Classes | Leading class | Share | Runner-up |
|---|---|---|---|---|---|
| electrical | 2,804 | 40 | Class 9 · Software & electronics | 29% | Class 11 · 18% |
| medicated also medication | 2,384 | 34 | Class 10 · Medical devices | 30% | Class 5 · 28% |
| computer | 1,384 | 26 | Class 9 · Software & electronics | 38% | Class 42 · 36% |
| vehicle | 1,231 | 33 | Class 12 · Vehicles | 44% | Class 37 · 11% |
| consulting | 876 | 11 | Class 35 · Retail, ads & business | 24% | Class 42 · 18% |
| water | 855 | 34 | Class 11 · Lighting & appliances | 23% | Class 32 · 8% |
| auto | 754 | 36 | Class 12 · Vehicles | 18% | Class 9 · 16% |
| cloth also clothing, clothes | 736 | 32 | Class 25 · Clothing | 19% | Class 24 · 12% |
| manufacturing | 701 | 25 | Class 1 · Industrial chemicals | 29% | Class 40 · 19% |
| automation | 697 | 34 | Class 12 · Vehicles | 18% | Class 9 · 17% |
| building | 681 | 24 | Class 37 · Construction & repair | 33% | Class 19 · 27% |
| 677 | 24 | Class 16 · Paper & printed goods | 44% | Class 9 · 15% |
The pairs are worth reading closely. computer splits almost evenly between Class 9 and Class 42, which is the goods-versus-services line that catches software businesses: the program is a good, the service of running it is not. clothing leads in Class 25, the garments class, with less than a fifth of its descriptions, because the fabric, the retail service and the manufacturing service are all elsewhere.
The same measure, inverted: words whose leading class holds nearly everything.
| Word | Descriptions | Leading class | Share |
|---|---|---|---|
| custom manufacturing | 108 | Class 40 · Manufacturing & processing | 98% |
| hand tool | 256 | Class 8 · Hand tools | 96% |
| entertainment | 453 | Class 41 · Education & entertainment | 94% |
| brokerage | 120 | Class 36 · Finance & insurance | 94% |
| cardboard | 203 | Class 16 · Paper & printed goods | 93% |
| business consulting | 122 | Class 35 · Retail, ads & business | 93% |
| stationery | 102 | Class 16 · Paper & printed goods | 91% |
| legal | 172 | Class 45 · Legal & security services | 91% |
These are the terms that behave the way classification is usually described, and they have something in common: each already names a service or an article precisely rather than a material or a category. That is the practical lesson in one line. The more precisely an identification describes what is actually sold, the fewer classes it could belong to, and the less room an examiner has to disagree with the one you chose.
A registration covers the goods and services named in it, and nothing else. File in the wrong class and the registration protects things you do not sell while leaving what you do sell unprotected, at full price, since the USPTO charges per class. An identification cannot be broadened after filing either, so the choice is made once.
It also explains a common piece of bad advice. "You are in a different class, so you are fine" is not a rule an examiner applies: likelihood of confusion is judged on the identifications, not the class numbers, which is why a conflict can sit in a class nobody thought to look at. The same name in a different industry covers that directly.
Source: the USPTO Trademark ID Manual, the office's list of pre-approved identifications, held locally as 64,313 entries and queried with SQLite full-text search. The vocabulary tested is the 620 ordinary goods and services words, from an internally maintained list, that return at least 25 accepted descriptions each; words returning fewer are excluded because a handful of descriptions cannot show a spread. For each word, every accepted description containing it is grouped by class; "classes" is the number of distinct classes returned and "share" is the largest class's count divided by the total. Every figure on this page is computed when the page is served, so it reflects the manual as currently loaded rather than a snapshot typed in at publication.
Limits, stated plainly. Matching is by prefix, so "clothing" also matches inside "non-clothing", which inflates spread slightly for words that appear in negative phrasings. A word appearing in a description is not the same as the description being about that word: "cases for mobile phones" counts toward both cases and phones, which is the intended behaviour here but is not a claim about what the item primarily is. The manual records what the USPTO has accepted, not what applicants file, so this measures the shape of the official vocabulary rather than filing behaviour. And the tested vocabulary is a curated list of ordinary words, not the full manual: it is chosen to reflect how people describe what they sell.
All 45 classes · How the class system works · Deadline calculator