Most people in the U.S. assume Energizer invented the pink battery bunny. They didn’t. Duracell did. And the reason Energizer owns the Energizer Bunny trademark in the U.S. today comes down to a missed trademark filing that cost Duracell exclusive rights to the mascot it created.
It’s a useful story for any business owner who has a registered trademark, because the lesson is straightforward: getting the trademark is only the start. Keeping it requires ongoing maintenance, and the cost of skipping that maintenance can be enormous.
Duracell Had the Bunny First
In 1973, Duracell launched a TV commercial featuring a row of pink toy bunnies drumming in unison. One by one, the bunnies powered by competing batteries stopped. The Duracell-powered bunny kept going. It was a simple, effective concept, and Duracell ran variations of it for roughly 15 years.
During that time, the pink drumming bunny became closely associated with Duracell. Consumers saw a pink bunny and thought Duracell. That’s exactly what a trademark is supposed to do, create a mental link between a symbol and a company.
But by 1988, Duracell had let its U.S. trademark registration on the pink drumming bunny lapse. The company stopped maintaining its claim to exclusive use in the United States.
How Energizer Got the Bunny Trademark
In late 1988, Energizer aired its first bunny commercial. It was structured as a parody of the Duracell format. A group of toy bunnies drummed on screen, mimicking the familiar Duracell setup. Then a larger pink bunny wearing sunglasses and flip-flops crashed through the scene, powered by Energizer batteries, and just kept going.
The ad was clever. It acknowledged the Duracell original while creating something new. And because Duracell’s U.S. trademark had lapsed, Energizer was free to file its own trademark application for a pink battery bunny in the United States.
Duracell tried to file after Energizer but was blocked by Energizer’s prior application. In trademark law, timing matters. Energizer filed first, and that filing gave them priority.
The Settlement That Split the World
By January 1992, the two companies reached a confidential settlement. The terms divided the territory:
- Energizer got exclusive rights to the battery bunny in the United States and Canada.
- Duracell got exclusive rights everywhere else.
That’s why, if you travel outside North America, you’ll see Duracell’s pink bunny on packaging and in advertisements. Inside the U.S. and Canada, it’s Energizer’s bunny. Two nearly identical mascots coexisting in separate markets because of a legal settlement.
The dispute didn’t end there. In February 2016, Energizer sued Duracell, alleging that Duracell bunny products had appeared in U.S. retail stores, violating the 1992 agreement. The case went through U.S. District Court, with partial summary judgment granted to Duracell in October 2017. The underlying tension between these two companies over a pink bunny has lasted decades.
What Went Wrong: Trademark Abandonment in Action
Duracell didn’t lose its bunny because of a lawsuit or a competitor’s superior legal strategy. It lost the bunny because it didn’t maintain its trademark registration.
Under U.S. trademark law, trademark abandonment happens when an owner deliberately stops using a mark with no intention of picking it back up. If three consecutive years pass without use, courts presume abandonment, and the burden shifts to the owner to prove they still planned to use it. On top of that, letting a registration lapse by missing maintenance filings can leave you without the federal protections that come with registration.
Letting a trademark lapse is like letting your lease expire and being surprised when someone else moves in. The space doesn’t stay empty, waiting for you to come back. Someone else takes it. This is one of the most common legal traps businesses fall into.
What Trademark Renewal Actually Costs
One reason trademark registrations lapse is that business owners don’t realize ongoing filings are required. Registering a trademark isn’t a one-time event. The USPTO requires periodic maintenance filings to confirm you’re still using the mark.
Here’s what that looks like in 2026:
- Section 8 Declaration of Continued Use: $325 per class. Due between years 5 and 6 after registration, then every 10 years.
- Section 9 Renewal Application: $325 per class. Due every 10 years.
- Combined Section 8 and Section 9 at the 10-year mark: $650 per class.
- Grace period surcharge (if you miss the deadline): $100 per class.
For comparison, the initial trademark filing costs $350 or more per class. The maintenance filings that follow are slightly less expensive than the original filing. For most businesses, we’re talking about a few hundred dollars every several years.
Now compare that to what Duracell lost. The company spent 15 years building consumer recognition around a pink battery bunny, only to hand that equity to a direct competitor. The brand value of an iconic mascot can run well into the multi-millions. The filing to keep it would have cost a few hundred dollars.
If you’re not sure what trademark protection actually gives you, it’s worth understanding before your next renewal comes due.
A Trademark Maintenance Checklist for Business Owners
If you have a registered trademark, or you’re planning to register one soon, here’s what ongoing maintenance looks like:
Track Your Filing Deadlines
- Year 5-6: File your Section 8 Declaration of Continued Use.
- Year 9-10: File your combined Section 8 and Section 9 renewal.
- Every 10 years after that: File the combined renewal again.
Missing these deadlines can result in cancellation of your registration. There’s a six-month grace period, but it comes with a $100 surcharge per class, and you shouldn’t rely on it as a backup plan.
Keep Using Your Mark in Commerce
A trademark registration protects a mark you’re actively using. If you stop using the mark, the registration becomes vulnerable to cancellation, even if you’ve filed all the paperwork. Use it on your products, packaging, website, and marketing materials consistently.
Monitor for Infringement
Your trademark registration gives you the right to stop others from using confusingly similar marks. But the USPTO won’t do that monitoring for you. Set up alerts for your brand name and key terms. Watch for new trademark applications that are too close to yours.
Update Your Contact Information
The USPTO sends correspondence to the address on file. If your business moves or your attorney of record changes, update that information. Missed notices can lead to missed deadlines.
Keep Records of Use
Save dated examples of your mark in use: product photos, packaging, advertisements, website screenshots. If someone ever challenges your registration, you’ll need evidence that you were actively using the mark during the relevant time period.
Why the Energizer Bunny Trademark Story Matters for Startups
If you’re building a company, your brand is one of your most valuable assets. The name, the logo, the identity you’re creating, all of that carries value that grows over time. Protecting it with a trademark registration is an important step. But the registration is only the beginning.
The risks of leaving your IP unprotected go beyond just trademarks. Duracell built 15 years of brand equity around a pink bunny and lost exclusive U.S. rights because of a lapsed filing. Energizer, to its credit, recognized the opportunity and moved fast. That’s how a competitor ended up owning a mascot it didn’t create.
Many brand owners make similar mistakes without realizing it. Your brand might not be worth as much as the Energizer Bunny (at least not yet). But the principle is the same. A few hundred dollars in maintenance filings every few years protects an asset that could be worth far more than that.
FAQs
Yes. If you don’t file the required maintenance documents with the USPTO, your registration will be cancelled. Once cancelled, the mark becomes available for others to claim. Duracell’s experience with the pink bunny is a real-world example of exactly this happening.
The combined Section 8 and Section 9 filing at the 10-year mark costs $650 per class in 2026. Between years 5 and 6, you’ll file a Section 8 Declaration of Continued Use for $325 per class. These are USPTO fees and don’t include attorney fees if you use one.
Trademark abandonment occurs when a mark’s owner stops using it in commerce without intent to resume use. Under U.S. law, three consecutive years of non-use creates a legal presumption of abandonment. Abandonment can also happen when a registration lapses due to missed maintenance filings.
Not exactly. Duracell created the original pink drumming bunny concept in 1973. Energizer launched its own version as a parody in late 1988, after Duracell’s U.S. trademark had lapsed. Energizer then filed for its own trademark and secured exclusive U.S. rights through a 1992 settlement agreement. It was legally permissible because Duracell had stopped maintaining its claim.
Yes. Under the 1992 settlement, Duracell retained exclusive rights to the battery bunny outside the United States and Canada. If you travel to Europe, Asia, or most other markets, you’ll see Duracell’s pink bunny on packaging and in ads.
Next Steps
If you have a registered trademark and you’re not sure whether your maintenance filings are up to date, I’d be happy to take a look. It’s a quick check that can save you a lot of headaches down the road.
Here’s a link to my calendar. Feel free to grab a time that works for you.
