Trademark Rights Under Common Law

Picture two coffee roasters who have never met and never will. One opens a tiny shop in Asheville, North Carolina, in 2019 and calls her beans "Mockingbird Coffee." She paints a hand-lettered sign, prints bags, and builds a loyal local following. Eight hundred miles away, in 2021, a different roaster opens "Mockingbird Coffee" in Austin, Texas, with no idea the Asheville shop exists. Neither has registered anything with the government. Neither has a lawyer on retainer. Each one genuinely believes the name is hers.

Who owns "Mockingbird Coffee"?

The honest answer—both of them, sort of, in different places—is one of the most surprising and least understood features of American trademark law. In the United States, you can own enforceable trademark rights without ever filing a single form, paying a single fee, or registering with any agency, state or federal. You get those rights the old-fashioned way: by using your mark in the marketplace. Lawyers call these common law trademark rights, and they are the bedrock on which the entire trademark system is built. Registration, as powerful as it is, is largely a way of supercharging rights that use created in the first place.

This article is a thorough, plain-English tour of common law trademark rights: where they come from, exactly what they protect, how far they reach geographically (the answer is the heart of the whole subject), how to mark and prove them, how they can be lost, and how they collide with the federal registration system when the two worlds meet. Whether you are a founder choosing a name on a napkin, a lawyer briefing a priority dispute, or a judge sorting out who got there first, you should come away knowing how unregistered rights work, where they fail, and when it is time to upgrade. Along the way we will meet two long-dead litigants whose 1918 fight over a medicine called "Rex" still decides cases today, and a doctrine with the wonderful name of Tea Rose-Rectanus.

If you want the gentler on-ramp to trademarks generally—what a mark is, the difference between ™ and ®, the spectrum of strong and weak marks—start with our companion piece on trademark basics and circle back here. If you already know the fundamentals, settle in.

What "Common Law" Means Here (and Why Trademarks Started There)

"Common law" is one of those phrases that sounds vaguely majestic and explains nothing. In context it simply means judge-made law that developed through court decisions over centuries, rather than rights conferred by a statute. Long before Congress ever passed a federal trademark act, English and American courts protected merchants against rivals who tried to pass off their own goods as someone else's by copying a distinctive name or mark. The original wrong was not "infringing a registration"—there were no registrations. The wrong was deception: tricking the buying public into thinking Brand X's goods came from Brand Y. The remedy grew out of the old tort of "passing off" (sometimes "palming off"), and the underlying goal has never really changed. Trademark law exists to protect the public from confusion about who is responsible for a product, and to protect the honest seller's hard-won reputation—what the law calls goodwill—from being hijacked.

That history matters because it explains a principle that trips up almost everyone who comes from a patent or copyright background: a trademark is not a thing you invent and then own in the abstract. It is a relationship between a symbol and a source, and that relationship only exists where the public has actually experienced it. You do not "create" a trademark by thinking it up, sketching it, or even spending a fortune designing it. You create it by using it on goods or services in the marketplace so that consumers come to associate it with you. No use, no mark. This is why the U.S. system is, at its core, a "first to use" system rather than a "first to file" system—a deep difference from patents and from trademark regimes in much of the rest of the world (more on that contrast below).

The Lanham Act, the modern federal trademark statute enacted in 1946 and codified at 15 U.S.C. § 1051 and following, did not abolish common law rights. It built a registration system on top of them, layering federal benefits over the use-based foundation. The Act expressly preserves common law rights in several places, and its very definition of a trademark turns on use: a mark is a word, name, symbol, or device used "to identify and distinguish" one person's goods from another's and "to indicate the source" of those goods (15 U.S.C. § 1127). Use is the engine. Registration is the turbocharger. The two operate side by side: state law continues to recognize common law trademark and unfair-competition rights that "arise from using the mark in commerce in the state" and "typically extend only to the territory where the mark is used," exactly as they did before 1946.

How You Get Common Law Rights: Use in Commerce

The triggering act is use in commerce—using the mark in connection with actually selling or offering goods or services to the public, in a way that consumers see and rely on. For a product, that classically means the mark appears on the goods themselves, their packaging, labels, or tags, and the goods are sold or transported in commerce. For a service (where the source identifier is technically a service mark, though everyone loosely calls it a "trademark"), use means displaying the mark in the sale or advertising of services that you are actually rendering—on your signage, website, menus, invoices, ads, and the like.

A few features of this rule deserve unpacking, because the details decide cases.

Use must be bona fide and in the ordinary course of trade. A token shipment to a friend, a single sham sale staged to manufacture rights, or a mark slapped on a mock-up that never reaches a real customer generally will not do. Courts want genuine commercial use, not a paper trail engineered by a lawyer. The Lanham Act codified this for registration purposes—"use in commerce" means "bona fide use…in the ordinary course of trade, and not made merely to reserve a right in a mark" (15 U.S.C. § 1127)—and the same spirit animates common law analysis. Importantly, this is the same bona-fide-use standard that the Act applies on the back end: maintaining trademark rights requires the same genuine commercial use that creating them does, which is why a mark left idle eventually evaporates (a point we return to under abandonment).

Priority runs from your first use, and it is continuous use that keeps it alive. The senior (earlier) user generally beats the junior (later) user. But "first use" is itself a contested fact in many disputes, and the date you can prove matters far more than the date you privately believe. Courts also recognize a doctrine called analogous use (sometimes "use analogous to trademark use"): pre-sales activity such as advertising, promotional mailings, or trade-show displays that creates a public association between the mark and the source can, in some circuits, establish priority slightly ahead of the first actual sale—provided the technical trademark use follows within a commercially reasonable time. The takeaway for the careful brand owner is to document the earliest public-facing use of the mark, not merely the first invoice.

The mark has to be capable of functioning as a source identifier. Common law rights, like registered rights, attach more readily to distinctive marks. Fanciful and arbitrary marks ("Kodak" for film; "Apple" for computers) and suggestive marks are protectable the moment they are used. Descriptive terms ("Creamy" for yogurt), geographic terms, and personal surnames are only protectable once they acquire secondary meaning—proof that the public has come to associate the term with a single source rather than its ordinary meaning. Generic terms ("Coffee" for coffee) can never be trademarks, registered or not; a mark can even fall into genericness over time (think "escalator" or "aspirin") and lose all protection. The famous framework for sorting marks along this spectrum comes from Abercrombie & Fitch Co. v. Hunting World, Inc., 537 F.2d 4 (2d Cir. 1976). For a fuller treatment of the distinctiveness spectrum and how to pick a strong name, see the trademark process, which walks the same ladder from generic to fanciful; and for the special problem of building a brand around a personal name, see trademarking your own name.

Put simply: the moment our Asheville roaster started selling "Mockingbird Coffee" bags to real customers in 2019, she owned a common law trademark. She did not need anyone's permission, and she did not need a certificate. The hard questions are not whether she has rights—she plainly does—but how strong they are and how far they reach.

The Core Trade-off: Strong Engine, Short Range

Here is the bargain at the center of common law rights, the thing to tattoo on your forearm before any priority fight:

Common law trademark rights are real and enforceable, but their geographic scope is limited to the territory where you have actually used the mark and built a reputation—plus, in some courts, a modest zone of natural expansion. They do not automatically blanket the entire country.

Federal registration changes that calculus dramatically, which is why we will spend real time on it later. But the unregistered baseline is territorial, and that single word explains the coffee-shop puzzle, the Rex medicine case, and most of the genuine disputes that walk into a trademark lawyer's office.

To see why, you have to understand the most important geographic doctrine in all of trademark law.

The Tea Rose-Rectanus Doctrine: Two Cases, One Rule That Still Governs

The geographic limits of unregistered marks were forged in two early-twentieth-century Supreme Court decisions decided two years apart and woven together in the lower courts ever since. Lawyers fold them into a single phrase: the Tea Rose-Rectanus doctrine.

Hanover Star Milling and the "Tea Rose" half

In Hanover Star Milling Co. v. Metcalf, 240 U.S. 403 (1916), competing flour millers each used the mark "Tea Rose" for flour, in good faith, in different parts of the country with no knowledge of each other. The Supreme Court held that a trademark is not a right in the abstract word; it is a right that exists only in connection with the goodwill of a business in the territory where the mark is used. As the Court memorably put it, the right to a trademark "grows out of its use, not its mere adoption." Where two parties had each innocently built up trade under the same mark in separate, remote markets, neither could oust the other from its own turf. The senior user's rights stopped at the edge of the senior user's market. The Court's reasoning is the conceptual root of the entire territoriality principle: because a mark only protects goodwill, and goodwill is local, the mark's reach is local too.

United Drug v. Rectanus and the "Rectanus" half

The companion case—and the one most often cited by name—is United Drug Co. v. Theodore Rectanus Co., 248 U.S. 90 (1918). The facts are almost a parable. A Massachusetts woman named Ellen Regis began using the mark "Rex" for a medicinal preparation in the Northeast around 1877, and her business (eventually United Drug) grew over the decades. Meanwhile, around 1883, a druggist named Theodore Rectanus, in Louisville, Kentucky, started using the very same mark "Rex" for his own medicine—entirely independently, in complete good faith, with no knowledge whatsoever of the Regis use far away in New England. For years the two marks coexisted in their separate corners of the country, each building local goodwill, neither aware of the other.

When United Drug finally pushed into the Louisville market and tried to stop Rectanus from using "Rex" there, the Supreme Court said no. Justice Pitney's opinion laid down the rule that controls to this day: the prior user's rights do not automatically extend into a remote geographic market where a later user has, in good faith and without knowledge of the senior user, adopted and built up the same mark first. In that remote territory, the good-faith junior user—not the technically-senior user—has the superior right. The senior user cannot use its earlier first-use date as a sword to reach into a distant market it never served, to dispossess an innocent local user who got there first locally.

The Court grounded this in the nature of a trademark itself. A trademark "is not property in the ordinary sense," Justice Pitney wrote; it is merely a means of protecting the goodwill of a business, and "its function is simply to designate the goods as the product of a particular trader and to protect his good will against the sale of another's product as his." Because Regis's goodwill had never reached Louisville, there was nothing in Louisville for her mark to protect—and Rectanus, who had built goodwill there, was entitled to keep it.

What the doctrine actually requires

Distilled, the Tea Rose-Rectanus doctrine lets a junior user defeat the senior user's claim in a particular geographic area if the junior user shows:

It adopted the mark in good faith, meaning without knowledge of the senior user's prior use; and
It used the mark in a geographically remote area, one the senior user had not penetrated; and
The senior user had not, at the time the junior user adopted the mark, established a market presence (or a reputation/zone of natural expansion) in that area.

The decisive ingredient, time and again, is good faith—and good faith collapses the instant the junior user knew about the senior user. Courts are divided on a subtle wrinkle here: some treat any knowledge of the senior user as fatal to good faith, while others ask whether the junior user adopted the mark with a wrongful intent to trade on the senior user's reputation. This split is exactly the terrain of our companion case study. In Stone Creek, Inc. v. Omnia Italian Design, Inc., 875 F.3d 426 (9th Cir. 2017), the Ninth Circuit drove home that knowledge of the senior user destroys the good faith the doctrine demands, so a junior user who copied a known mark cannot hide behind the "remote, innocent user" defense. If you are litigating or advising on a remote-use scenario, read our deep dive on Stone Creek v. Omnia and how knowledge destroys good faith under the Tea Rose-Rectanus doctrine; it is the modern, must-know application of the rule and the natural sequel to this article.

Back to the coffee shops

Now the "Mockingbird Coffee" puzzle solves itself. The Asheville roaster (2019) is the senior user nationally, but her common law rights are anchored to her actual market and reputation around western North Carolina. The Austin roaster (2021) adopted the same name independently and in good faith, with no knowledge of Asheville, in a remote market the Asheville shop never served. Under Tea Rose-Rectanus, the Austin shop is a good-faith remote junior user; it can keep using "Mockingbird Coffee" in its Texas territory. Neither can stop the other on home turf. Each owns the same name—in a different place. They are, in effect, two separate trademarks that happen to look identical.

That uneasy coexistence works fine until someone tries to expand, or until someone files for a federal registration—and that is where the story gets interesting, because the federal system rewrites the geography.

Marking Your Common Law Rights: TM and SM (and Why ® Is Off-Limits)

Before we get to the federal collision, a practical word about symbols, because using the wrong one is a surprisingly common—and occasionally costly—mistake.

The ™ symbol signals a claim of trademark rights in goods. The ℠ symbol ("SM," for service mark) signals a claim of rights in services. You may use ™ or ℠ freely, anytime, without registering anything, to announce that you regard a term, logo, or slogan as your mark. There is no application, no fee, and no approval required. Using ™ or ℠ does not by itself create rights—remember, use creates rights—but it serves two useful functions: it puts the world on notice that you claim the mark, which can deter copycats and undercut a later user's claim of good-faith innocence; and it helps establish that you are using the term as a mark rather than as an ordinary descriptive word, which matters when you later try to prove distinctiveness or secondary meaning.

The ® symbol is different and legally restricted. The federal registration symbol may be used only with marks that are actually registered on the Principal Register at the U.S. Patent and Trademark Office (USPTO), and only for the goods or services covered by that registration. Using ® on an unregistered mark—or on goods outside your registration—is improper. It can be treated as a misrepresentation, and in litigation a knowing misuse of ® can bar a plaintiff from certain remedies, because a party who deceives the public about its registration status may be denied equitable relief under the unclean-hands doctrine. So the rule is simple and absolute: no federal registration, no ®. Until that certificate issues, your common law marks wear ™ or ℠.

(A nuance worth flagging: a pending federal application does not entitle you to ®. While your application sits at the USPTO, you are still an unregistered, common law owner for symbol purposes, and you stick with ™ or ℠ until registration actually issues.)

How Federal Registration Rewrites the Map

If common law rights are a hometown advantage, federal registration is a national broadcast. This is the single biggest reason to register, and understanding the mechanics is essential to understanding the limits of unregistered rights.

Constructive use and constructive notice: the date that freezes the country

When a federal application matures into a registration on the Principal Register, two Lanham Act provisions transform the owner's geographic position:

Constructive notice (15 U.S.C. § 1072). Registration is, by statute, constructive notice of the registrant's claim of ownership. In plain terms, the law treats the entire country as if it knew about your mark the day your registration issued—whether anyone actually did or not. This is lethal to the Tea Rose-Rectanus defense, because that defense depends on the junior user's good-faith lack of knowledge, and constructive notice erases the possibility of innocent later adoption anywhere in the U.S. After your registration issues, no newcomer can claim to be a good-faith remote user; they are charged with knowledge as a matter of law.
Constructive use / nationwide priority (15 U.S.C. § 1057(c)). When you file an application that later registers, the filing date counts as constructive use of the mark nationwide, giving you priority against almost everyone who had not already used the mark or filed before you. The registrant effectively plants a flag over the entire United States as of the filing date, even in places where it has not yet sold a thing.

Together, §§ 1057(c) and 1072 convert a use-based, territory-bound right into a presumptive nationwide right. A registrant in southern California can stop a newcomer from adopting a confusingly similar mark for similar goods in San Francisco, New York, or Anchorage—places the registrant has never operated—because the law now treats its rights as coast-to-coast.

This is also where the intent-to-use (ITU) application earns its keep. An ITU application lets you file based on a bona fide intention to use a mark you have not yet launched; if the mark ultimately registers, the application's filing date is treated as your constructive first-use date, "providing a priority date that is earlier than the first actual use." In a first-to-use country, the ITU mechanism is the closest thing to a reservation system—a way to claim the line at the front of the queue before you have sold anything. Our companion explainer on when to trademark your brand digs into why founders should usually lock in that nationwide priority date sooner rather than later.

The other federal perks

Beyond geography, registration on the Principal Register confers a stack of benefits that common law owners simply do not have (the Lanham Act collects most of them; see 15 U.S.C. §§ 1057, 1065, 1072, 1115, 1124):

Prima facie evidence of validity, ownership, and the exclusive right to use the mark nationwide (15 U.S.C. § 1057(b), § 1115(a)). In court, the registration certificate does a lot of the plaintiff's work for it.
The path to "incontestable" status after five years of continuous use (15 U.S.C. § 1065), which forecloses many challenges and makes the registration conclusive evidence of the exclusive right to use the mark (15 U.S.C. § 1115(b)). Crucially, incontestability also forecloses a challenge that the mark is "merely descriptive"—a defense that remains fully available against an unregistered descriptive mark.
Access to federal court and the Lanham Act's remedies, including the possibility of enhanced damages and attorneys' fees in exceptional cases.
The ® symbol, with its deterrent value.
Customs recordation to block the importation of infringing and counterfeit goods (15 U.S.C. § 1124).
A public record in the USPTO database that shows up in everyone else's clearance searches, deterring conflicts before they start.
A foundation for international registration through the Madrid Protocol.

By contrast, the common law owner must prove, from scratch and with evidence, that the mark exists, that it is distinctive, when first use occurred, and how far the territory extends—every single time. That is a heavy and expensive lift, and it is the practical reason most serious brands eventually register. For the step-by-step of getting there, see the trademark registration guide and how to file a trademark application with the USPTO.

When the Two Worlds Collide: Frozen Rights, Concurrent Use, and Dawn Donut

So what happens to the unregistered owner when someone else registers the very mark the unregistered owner has been using? This is where common law rights show both their resilience and their limits.

The senior common law user is grandfathered—but frozen

Suppose our Asheville roaster never registers, but the Austin roaster does—filing in 2022 and obtaining a federal registration for "Mockingbird Coffee." Does Austin's nationwide registration wipe out Asheville's earlier rights?

No. The Lanham Act protects a prior user whose use predates the registrant's filing. Even an incontestable registration is subject to the defense of a party who used the mark continuously from a date prior to the registrant's constructive-use (filing) date, and that prior user retains rights in the area where it used the mark before the registration (15 U.S.C. § 1115(b)(5)). Courts often describe this as the senior common law user being "frozen": it keeps its territory as of the registrant's filing date, but—because constructive notice now blankets the country—it generally cannot expand beyond that pre-existing territory. The registrant owns everywhere else.

So Asheville keeps western North Carolina (its established market as of Austin's 2022 filing), but it loses the ability to grow into, say, Charlotte or Raleigh under that name if those areas were not yet part of its market. Austin, the junior-but-registered user, owns the rest of the country. This is precisely why prompt registration is so valuable: had Asheville registered first in 2019, it would have owned the nationwide priority date and Austin's later use would have been junior everywhere. The roaster who files converts a hometown right into a national one; the roaster who merely uses keeps only the hometown.

Concurrent use: drawing the map at the USPTO

Sometimes two good-faith users each have legitimate, geographically separate rights, and the system formalizes the split through a concurrent use registration. The Lanham Act expressly allows concurrent registrations to issue to more than one party when confusion is unlikely because the parties use the mark in distinct territories or conditions (15 U.S.C. § 1052(d)). A concurrent-use proceeding before the Trademark Trial and Appeal Board (TTAB) can carve the country into zones, awarding each user a defined territory on the federal register. It is the legal equivalent of two siblings drawing a line down the middle of a shared room.

The classic illustration is Burger King of Florida, Inc. v. Hoots, 403 F.2d 904 (7th Cir. 1968). A family named Hoots had opened a "Burger King" restaurant in Mattoon, Illinois, and even held an Illinois state registration—before the now-ubiquitous national Burger King chain obtained its federal registration. The court held that the Hoots family could keep using "Burger King," but only within the narrow market area they had actually served before the national chain's federal registration (roughly a 20-mile radius around Mattoon). Everywhere else in Illinois—and the country—belonged to the federally registered national chain. The senior local user survived; it just survived in a very small box. (For decades, that lone Mattoon Burger King operated independently, a living monument to frozen common law rights.) Note, too, that a state trademark registration does not grant nationwide rights. As a leading practice treatise puts it, state registrations "generally grant rights no greater than those obtained under common law"—they provide constructive notice within the state and surface in search reports, but they are bounded by the state, and they lose to a federal registration outside the registrant's actual prior-use territory.

The Dawn Donut wrinkle: confusion only where markets overlap

One more classic deserves mention because it complicates the "nationwide rights" picture in a practical way. In Dawn Donut Co. v. Hart's Food Stores, Inc., 267 F.2d 358 (2d Cir. 1959), a federal registrant sought to stop a remote user, but the registrant was not actually doing business in the junior user's market. The Second Circuit held that even though the registration carried nationwide constructive rights, the registrant could not obtain an injunction against a geographically remote good-faith user until the registrant actually expanded into (or showed imminent plans to enter) that market—because, absent any market overlap, there was no present likelihood of confusion to enjoin. The "Dawn Donut rule" means a registrant's nationwide priority is not always the same thing as a present right to injunctive relief everywhere; relief tracks where confusion is actually likely. Some judges and commentators have questioned whether the rule still fits a national-internet economy in which almost everyone reaches everyone, and a few opinions have chipped at it, so treat it as unsettled at the edges—but the core insight, that likelihood of confusion is territorial and fact-specific, remains very much alive.

The upshot of this whole section: federal registration relocates the contest from "who used it first, where" to "who filed first, with grandfathered pockets for prior users." Common law rights survive that transition, but they survive as islands.

How Common Law Rights Are Lost (and a Registration Can Die but Common Law Rights Live On)

Common law rights are not just hard to prove—they can be lost, sometimes through the owner's own carelessness. Because the whole right rests on the link between mark and source, anything that severs or dilutes that link can destroy it. Three mechanisms account for most complete losses, and a fourth merely shrinks the right.

Abandonment through nonuse. Trademark rights are "use it or lose it" in a literal, statutory sense. The Lanham Act deems a mark abandoned when "use has been discontinued with intent not to resume" (15 U.S.C. § 1127). Three consecutive years of nonuse creates a rebuttable presumption of abandonment, which shifts the burden of production to the owner to show an intent to resume bona fide commercial use—though the ultimate burden of persuasion stays with the challenger. The same bona-fide-use standard that births a common law right also keeps it alive, so token, sporadic, or merely defensive use will not preserve an otherwise dormant mark.

Abandonment through uncontrolled ("naked") licensing. If you license your mark to others but fail to exercise meaningful quality control over the goods or services they sell under it, the mark stops reliably indicating a single source—and courts can find you have abandoned it entirely. The same fatal logic applies to an assignment in gross: a trademark transferred without the underlying goodwill of the business it symbolizes conveys nothing, because there is no goodwill for the mark to carry to its new owner.

Genericide. A mark can be loved to death. When the public comes to use the brand name as the generic term for the product category itself—"aspirin," "escalator," "thermos"—the mark loses its source-identifying significance and falls into the public domain, registered or not. Owners fight this with brand-style guidelines, "the [BRAND] brand of [product]" advertising, and policing. (For the mechanics of genericness challenges, the doctrine overlaps heavily with the distinctiveness analysis in trademark basics.)

Failure to police (erosion, not death). Letting third parties use confusingly similar marks unchecked usually does not abandon a mark outright, but it can erode the mark's strength and narrow its scope of protection, making it harder to enforce—see, for example, Sweetheart Plastics, Inc. v. Detroit Forming, Inc., 743 F.2d 1039 (4th Cir. 1984). Enforcement, in other words, is not optional housekeeping; it is part of what keeps the right alive.

Here is a counterintuitive payoff that confuses many businesses: a federal registration can be cancelled while the underlying common law rights survive. If a registration is cancelled—say, for a procedural defect or even for fraud in its procurement—the owner loses the statutory presumptions and benefits of registration but "may continue to have enforceable common law trademark rights in the geographic area where the owner uses the mark." The registration is a layer of armor over the use-based right; strip the armor away and the use-based right is still standing (wherever genuine use continued). This is the clearest possible illustration that, in American trademark law, use is the foundation and registration is the superstructure.

Common Law vs. "First to File": Why the Rest of the World Looks Different

Step back for a moment, because the U.S. approach is genuinely unusual. Most of the world runs a first-to-file system: whoever registers a mark first generally owns it, regardless of who used it first in the market. In those jurisdictions, prior unregistered use offers little or no protection, and "trademark squatting"—registering someone else's brand before they enter the country—is a real and recurring hazard for U.S. companies expanding abroad.

The U.S. first-to-use rule flips that priority. Use comes first; registration confirms and amplifies it. The practical lesson cuts two ways. Domestically, a startup that has genuinely been using a mark is not defenseless against a latecomer who races to the USPTO—prior use is a defense and, often, grounds to oppose or cancel. But the moment that same startup eyes foreign markets, the calculus inverts: it should file early and broadly abroad, because the goodwill it built at home may count for nothing overseas. American businesses sometimes carry their first-to-use instincts across the border and get a rude surprise; the cure is to treat international filing as a priority race, not an afterthought.

Proving It: The Practical Headache of Unregistered Rights

A common law right you cannot prove is, for litigation purposes, barely a right at all. This is the quiet tax on skipping registration: the burden of proof falls entirely on you, and the proof can be slippery.

Because there is no public record of an unregistered mark—no filing date, no certificate, no government acknowledgment—the common law owner must reconstruct its own history with evidence. To establish priority and scope you typically need:

Dated proof of first use in commerce for the specific goods or services: early invoices, sales receipts, dated product photographs, packaging, archived web pages (the Internet Archive's Wayback Machine is a courtroom regular), press coverage, and advertising with verifiable dates. On authenticating archived screenshots and web evidence in federal court, see our practitioner's guide to capturing the web and authenticating website screenshots as evidence.
Continuous use from that date forward—gaps invite an abandonment argument, and a three-year gap hands the other side a presumption.
Evidence of the geographic scope of sales and reputation: where customers are, where ads ran, shipping records, and market data. Remember, your rights extend only as far as your use and reputation reach.
Evidence of distinctiveness or secondary meaning, especially if the mark is descriptive, geographic, or a surname: survey evidence, length and exclusivity of use, advertising spend, sales volume, unsolicited media, and proof that consumers associate the term with you.

Contrast that with the registrant, who walks into court, hands the judge a certificate, and is presumed to own a valid, exclusive, nationwide mark (15 U.S.C. § 1057(b), § 1115). The common law plaintiff must build that presumption brick by evidentiary brick. It is doable—courts enforce unregistered marks every day—but it is slower, costlier, and riskier. This evidentiary asymmetry is the most underrated reason to register. A practical corollary: keep records from day one. The cheapest insurance a common law owner can buy is a clean, dated archive of first use, advertising, and sales by region—the very evidence a litigated priority dispute will demand years later.

Enforcing Common Law Rights: Yes, You Can Sue

Owning an unregistered mark does not consign you to helplessness if a copycat appears. There are real teeth here.

Lanham Act § 43(a) (15 U.S.C. § 1125(a)) is the great equalizer. It creates a federal cause of action for using a mark in a way "likely to cause confusion" as to source, sponsorship, or affiliation—and crucially, it protects unregistered marks, not just registered ones. So a common law owner can sue in federal court for trademark infringement and unfair competition under § 43(a), invoking the federal courts and federal remedies, even without a registration certificate. The owner must still prove it owns a protectable mark (distinctiveness) and that the defendant's use creates a likelihood of confusion—the central test of infringement, assessed through multi-factor analyses like the Polaroid, Sleekcraft, or DuPont factors depending on the circuit. Section 43(a) is also the vehicle for trade-dress and false-association claims, and it overlaps with false-advertising theory; for the competitor-claims side of § 43(a), see false advertising and Lanham Act Section 43(a). For a deeper treatment of the confusion analysis and the brand-owner considerations around it, see navigating the maze of trademark confusion.

State law adds another layer. Every state recognizes common law trademark and unfair-competition claims—including causes of action for unfair competition, passing off, and (in many states) dilution—and every state operates a trademark office that, "with varying requirements, provides for registration in that state." State registration is cheaper and faster than federal, provides constructive notice within the state, and surfaces in clearance searches, but it does not confer nationwide rights or federal constructive notice. It is best understood as a modest, in-state supplement to common law rights, not a substitute for federal registration.

The cease-and-desist letter is the most common first move, and an unregistered owner can absolutely send one—asserting common law rights, identifying the infringing use and the likelihood of confusion, and demanding that the junior user stop. (Tone and strategy matter enormously here, including the risk of provoking a declaratory-judgment lawsuit or earning a reputation as a "trademark bully.") Our guide to drafting a trademark cease-and-desist letter covers how to do it well, and if you are on the receiving end, read responding to a trademark cease-and-desist letter—where the strength and geographic reach of the sender's common law rights is often the whole ballgame.

And do not forget the affirmative duty that comes with ownership: trademarks must be policed. If you allow others to use confusingly similar marks unchecked, you risk weakening your mark or even abandoning it. Enforcement is not optional housekeeping; it is part of what keeps the right alive.

A Worked Example: Three Roasters and a Reckoning

Let us push the coffee hypothetical to its breaking point to see every doctrine fire at once. (All parties are invented; this is a hypothetical.)

Asheville Mockingbird (2019): first user nationally, common law rights in western North Carolina, never registered.

Austin Mockingbird (2021): independent, good-faith adopter; common law rights in central Texas; files for federal registration in 2022 and registers in 2023.

Denver Mockingbird (2024): a third roaster opens in Colorado, having Googled the name first and seen the Austin federal registration, but figuring Colorado is far away and decides to use it anyway.

Now apply the rules:

Asheville vs. Austin. Both are good-faith remote users under Tea Rose-Rectanus; each owned its territory. When Austin registered in 2023, Asheville became a frozen senior user under § 1115(b)(5)—it keeps western North Carolina as of Austin's 2022 filing date but cannot expand under the name. Austin owns the rest of the country going forward.
Austin vs. Denver. Denver is doomed. Because Austin's registration issued in 2023, constructive notice under § 1072 charges Denver with knowledge as a matter of law as of 2024—and Denver actually had real knowledge, having seen the registration. Denver cannot claim good-faith remote use; the Tea Rose-Rectanus defense is unavailable on both constructive and actual grounds. This is the Stone Creek lesson in miniature: knowledge destroys good faith. Austin can stop Denver nationwide (subject to Dawn Donut–style questions about whether confusion is presently likely if Austin has not entered Colorado).
Asheville vs. Denver. Interesting wrinkle: Asheville is the true national senior user, but its rights are territorial and frozen, and it never reached Colorado. As between these two, Asheville's unregistered rights do not reach Denver either—but it does not matter, because Austin's registration already covers Colorado, and Austin will be the one to enforce.

The moral, delivered three times in three cities: use creates rights; geography limits them; registration nationalizes them; and knowledge of someone else's mark forfeits the good faith that the remote-user defense requires. A clean clearance search at the start—checking the USPTO database, state registers, and common law sources like business directories and the open web—would have saved Denver entirely, and might have warned Austin and Asheville about each other. That is exactly why clearance is non-negotiable; see how to conduct a comprehensive trademark clearance search. And had any of the three secured a clearance opinion and a USPTO approval before launching, that paper trail could also help defeat a later claim of willful infringement—the subject of the shield of good faith.

So Why Does Anyone Stay Unregistered?

Given everything above, you might wonder why common law rights aren't just a way station everyone leaves as fast as possible. They are not nothing, and for some businesses they are genuinely enough:

They're free and automatic. No fees, no forms, no waiting. The corner bakery selling only to its neighborhood may never need more.
They cover marks that can't (yet) be registered—for instance, a descriptive term that hasn't yet acquired secondary meaning, or a mark a business is still testing in the market.
They protect you during the gap between launching a brand and the day a federal registration finally issues (which can take the better part of a year or more). In that interval, your common law rights are your only rights.
They back the § 43(a) claim that lets even unregistered owners reach federal court, and they survive even if a registration is later cancelled.

But the limits are real and they bite at exactly the wrong moments—when you grow, when you raise money (investors scrutinize trademark ownership during diligence), when you expand into new regions, or when a competitor with deeper pockets and a federal registration shows up in your market. As a rough rule of thumb: if your brand matters to your business, if you sell beyond a single locality (and anything online effectively does), or if you ever plan to scale, the modest cost of federal registration is one of the best returns in all of intellectual property. The unregistered baseline is a fine place to start; it is a risky place to stay.

Key Takeaways

Use, not registration, creates trademark rights in the U.S. The moment you use a distinctive mark in commerce, you own enforceable common law rights—no filing required. The U.S. is fundamentally a "first to use" jurisdiction, in contrast to the "first to file" systems that govern most of the world.
Common law rights are territorial. They reach only as far as your actual market and reputation, plus (in some courts) a small zone of natural expansion. They do not automatically cover the whole country.
The Tea Rose-Rectanus doctrine (from Hanover Star Milling, 240 U.S. 403 (1916), and United Drug Co. v. Theodore Rectanus Co., 248 U.S. 90 (1918)) lets a good-faith remote junior user keep its own territory against an earlier user who never reached that market.
Good faith is the linchpin, and knowledge destroys it—the core holding applied in Stone Creek v. Omnia, 875 F.3d 426 (9th Cir. 2017). A junior user who knew of the senior mark cannot claim the remote-user defense.
Use ™ or ℠ for unregistered marks; ® is reserved for federally registered marks only. Misusing ® can cost you remedies under the unclean-hands doctrine.
Federal registration nationalizes your rights through constructive use (15 U.S.C. § 1057(c)) and constructive notice (15 U.S.C. § 1072), and stacks on evidentiary presumptions, incontestability, federal remedies, customs help, and a public record. An intent-to-use application can secure that priority date before launch.
A senior common law user is grandfathered but "frozen" against a later federal registrant (15 U.S.C. § 1115(b)(5))—it keeps its prior territory but generally can't expand. Concurrent-use proceedings (illustrated by Burger King v. Hoots) can formalize the split, and Dawn Donut reminds us injunctive relief tracks where confusion is actually likely.
Common law rights can be lost through abandonment (including three years' nonuse, which raises a presumption), naked licensing, assignment in gross, or genericide—but they can also survive the cancellation of a federal registration.
Unregistered owners can still sue under Lanham Act § 43(a) (15 U.S.C. § 1125(a)) and under state law—but they bear the full burden of proving the mark, its distinctiveness, first use, and geographic scope.
Clearance first, register early. A thorough search avoids ugly priority fights, and prompt federal filing converts a hometown right into a national one.

Frequently Asked Questions

Do I have any trademark rights if I never registered anything? Yes. If you use a distinctive name, logo, slogan, or other source identifier in commerce, you automatically own common law trademark rights in the area where you use the mark and have built a reputation. You can enforce those rights, including in federal court under Lanham Act § 43(a) (15 U.S.C. § 1125(a)). The catch is that the rights are geographically limited and harder to prove than a registration.

Which symbol should I use—™, ℠, or ®? Use ™ for goods and ℠ for services to claim common law (unregistered) trademark or service mark rights; you may use these anytime, for free, with no filing. Use ® only if your mark is actually registered with the USPTO, and only for the goods or services in that registration. Using ® on an unregistered mark is improper and can cost you remedies in litigation. A pending application does not entitle you to ®.

If I used my mark first, do I automatically beat someone who registered it later? Not nationwide. As the senior common law user, you generally keep the territory where you used the mark before the other party's federal filing date—you become a "frozen" prior user under 15 U.S.C. § 1115(b)(5). But because the registration gives the registrant nationwide constructive rights, you usually cannot expand beyond your existing territory, and the registrant owns everywhere else. Registering first would have given you the nationwide priority.

What is the Tea Rose-Rectanus doctrine in one sentence? It is the rule that a good-faith user in a remote geographic market—one who adopted the mark without knowledge of an earlier user and built up trade there first—can keep using and defend that mark in its own territory, even against a technically senior user who never reached that market. It comes from Hanover Star Milling Co. v. Metcalf, 240 U.S. 403 (1916), and United Drug Co. v. Theodore Rectanus Co., 248 U.S. 90 (1918).

What if the later user knew about my mark when they started using it? Then they almost certainly lose the remote-user defense. The Tea Rose-Rectanus doctrine protects only good-faith adopters, and courts—most notably in Stone Creek v. Omnia—hold that knowledge of the senior user's mark destroys the good faith the defense requires. A copycat who knew of your mark cannot hide behind "I was far away."

Can I lose common law rights I never registered? Yes. Even unregistered rights can be lost through abandonment (three consecutive years of nonuse raises a presumption of abandonment), through naked licensing (licensing the mark without quality control), through assignment in gross (transferring the mark without its goodwill), or through genericide (the public turning your brand into the generic product name). Sustained, bona fide use and active policing are what keep the right alive.

Are common law rights worth anything against a big company with a federal registration? They can be, but within limits. If your use predates the company's federal filing date, you are a grandfathered prior user in your established territory (the Burger King v. Hoots scenario—the Hoots family kept their single Illinois restaurant). Outside that territory, the federal registrant generally wins. This is exactly why founders are urged to register early; see when to trademark your brand.

How do I prove my common law rights if there's no public record? You assemble evidence: dated invoices and receipts, product and packaging photos, advertising with verifiable dates, press coverage, archived web pages, and sales/shipping data showing where you operate. You may also need evidence of secondary meaning if your mark is descriptive, geographic, or a surname. This burden—entirely on you—is the practical downside of skipping registration, and a reason to register and to keep good records from day one.

Does a state trademark registration give me nationwide rights? No. A state registration provides statutory recognition within that state, layered on top of your common law rights, and it surfaces in clearance searches—but it does not confer the nationwide constructive notice or priority that a federal registration does. State registrations generally grant rights no greater than common law. Against a federal registrant outside your actual prior-use area, a state registration generally will not save you.

Is it ever fine to rely on common law rights alone? Sometimes—for a purely local business with no plans to expand, or during the months between launch and registration, common law rights may be adequate. But anything sold online effectively reaches a national market, and most growing brands quickly outrun the protection that unregistered rights provide. Treat common law rights as a solid starting point, not a permanent strategy.

This article provides general information about trademark law and is not legal advice. Trademark rights and disputes turn on specific facts and on law that varies by jurisdiction and changes over time. For advice about your situation, consult qualified counsel.