Trademarks help protect providers of products and services from unfair competition. An example of unfair competition is when company “A” sells a product or service, and business competitor “B” sells a competing product or service in such a manner as to confuse company “A” customers into accidentally buying from company “B”.
Three general principles of trademark law can be summed up as “don’t try to trademark the normal names of a product or service”, “a trademark only has meaning in the context of a particular class of product or service”, and “use it or lose it”.
Trademarks that too closely resemble the normal name of a product or service will be rejected as being “generic“. By contrast, a trademark that is “fanciful”, — that has no obvious correlation to a product or service, will often be accepted. Trademarks falling in between these two extremes, which may be “descriptive” of the underlying product or service, often will be put on probation in a “secondary trademark register” for 5 years. After 5 years of use in trade, absent objection by outsiders, the descriptive name can then be granted full trademark status on the “primary trademark register“.
Note that the word “Trademark” has the word “trade”. This begs the question, trade in what? Under both US and international trademark law, products and services are shoehorned into a limited number of different trademark classes. Although recycling the same names within a class is generally not tolerated, the same names can often be reused for alternate products or services between classes, so long as there is not confusion. The USPTO generally examines trademarks on a per class basis.
Trademarks are granted on a “use it or lose it” basis. Although it is possible to reserve trademarks (at least fanciful trademarks) for up to a few years on an “intent to use” basis, ultimately to get the trademark, you need to provide proof that the mark is actually being used in commerce by submitting a “specimen”. This is often a photograph of sales receipts, website purchase pages, and the like, showing that the trademark name is actually being used in real trade.
There are many other complexities of trademark law as well. Searches can be tricky, because the underlying legal standard for trademark infringement is “possibility of confusion”, and not “the same spelling“. Unregistered common law trademarks are another potential problem. Thus merely avoiding other trademarks with identical spelling is often not enough. Alternative spellings, word prefixes, word suffixes, and other name variations can often cause problems if potential customers might be confused.