Trademark rights in the US are based on use not registration. Trademark registration confers many valuable additional rights. So, NO lack of a Federal registration does not mean you can use, own or register that trademark. The TM symbol says "I claim this as my trademark." That does not mean the claim is correct or even legal. However, it tells you there is risk in using or trying to register that same mark for similar goods or services. You really need to go to www.uspto.gov and click on Trademarks and watch and listen to the entertaining videos and read the FAQs.
Now, having said all that, you need to know that in most foreign countries, rights are based on registration, so the answer may well be different in another country. An IP lawyer will know or can find out the relevant law on trademarks there.
I am not your lawyer and you are not my client. Free advice here is without recourse and any reliance thereupon is at your sole risk. This is done without compensation as a free public service. I am licensed in IL, MO, TX and I am a Reg. Pat. Atty. so advice in any other jurisdiction is strictly general advice and should be confirmed with an attorney licensed in that jurisdiction.
Q: "Can i use a trademark that hasnt actually been registered?"
R: The short answer is that unregistered trademarks are just as enforceable as registered trademarks.
You need to back up, however. Your question assumes that whatever it is that's branding the product or service really is a trademark -- or, if it is, that it really belongs to the person selling that product or service.
Lots of business folks do not know how to properly adopt and use trademarks. While the "tm" symbol puts everyone on notice that the person using the source-identifier claims trademark rights in that identifier that does not mean trademark rights actually attach to that identifier. No trademark rights exist, for example, in the phrase "The World's Best Apples" when used to sell apples even if the "tm" symbol is affixed to that phrase. Likwise, if a package delivery service adopts the phrase "We Try Harder" and affixes the "tm" symbol to it no trademark rights develop either because that phrase is already used as a trademark by someone else.
So ... it sounds like you want to brand a product or service with a trademark. Then speak with a trademark attorney to help you decide what mark to use, to then "clear the rights" the mark and to then learn how to use it in commerce properly. Good luck.
The above response is general information ONLY and is not legal advice, does not form an attorney-client relationship, and should NOT be relied upon to take or refrain from taking any action. I am not your attorney. You should seek the advice of competent counsel before taking any action related to your inquiry.
The specific answer greatly depends on whether your use would create market confusion as it relates to this other mark holder's market area and its natural expansion.
Whenever you endeavor into investing in a trademark it is very important that you conduct the proper clearance due diligence upfront and before you submit an application to the USPTO. In the US, this means searching under both federal (USPTO) as well as common law because trademark rights stem from use in this country NOT registration. This means that acquiring a federal registration does not necessarily mean that you are not infringing on another's intellectual property. See the link below for a detailed explanation of the due diligence process.
I suggest that you consult with a lawyer in private and discuss your objectives in more detail. You can start by calling around to several for a free phone consultation, get some insights then pick the best fit to work with.
DISCLAIMER: this is not intended to be specific legal advice and should not be relied upon as such. No attorney-client relationship is formed with the law firm of Natoli-Lapin, LLC on the basis of this posting.
As my colleagues have stated, the answer is that it depends. Trademark rights in the United States are based on first to use, not first to register and are limited to the class of goods and services that the trademark identifies. Registration grants nation-wide priority rights. Where a person does not have federal registration, they may have a state-specific registration or no registration at all. In the case of the latter situations, the rights are limited to a specific geographic region. If the trademark holder registers in a state, the geographic protection is for that entire state; if no state registration then you will want to consult with an attorney to identify the reach of the geographic protection afforded to that trademark.
You also want to ask whether you are going to be using the term for the same goods and/or services. For example, if you are going to be operating a dry cleaning business and the trademarked term is for dog grooming, there is an argument that the public would not confuse your two services because they are in very different categories of services. However, in all of this, the specifics around both the claimed trademark and your desired use should be discussed with an attorney.
The information provided in this answer is for informational purposes only and should not be construed as legal or expert advice which can only be obtained from appropriate professionals. Additionally, this answer does not create an attorney-client relationship.