Starting Point
You may have seen the name Cuthbert the Caterpillar popping up on social media or in the news recently. If you are wondering why a supermarket cake is trending, you are not alone. The story behind Cuthbert is one of the most entertaining, surprising, and genuinely clever brand moments in recent UK retail history. It has everything. A corporate lawsuit, a viral hashtag, a cake in prison bars, and a German supermarket that turned a legal attack into a public relations masterclass.
In this complete guide, we cover everything you need to know about Cuthbert the Caterpillar. Specifically, we explain what Cuthbert is, why M&S sued Aldi over it, how Aldi responded with one of the most brilliant social media campaigns in UK history, how the legal case ended, and why the story keeps coming back into public conversation years later. Whether you are new to the story or want to understand every chapter of it, this article covers it all.
What Is Cuthbert the Caterpillar?
Before getting into the legal drama, it helps to understand what Cuthbert actually is.
Aldi’s Chocolate Caterpillar Cake
Cuthbert the Caterpillar is Aldi’s much-loved chocolate sponge cake, known for its fun design, creamy filling, and accessible price point. Introduced in 2019, it quickly earned a place on UK celebration tables, especially for children’s birthdays.
Cuthbert features a chocolate-coated sponge with a sweet buttercream filling, decorated with colourful chocolate buttons and a cheerful white chocolate face. Retailing for just £6.99 at 625g, it offers a lower-cost alternative to its more famous rival. That price difference is central to the whole story. Aldi is a budget supermarket. M&S is a premium one. The gap between those two worlds is exactly where the conflict began.
The Caterpillar Cake Tradition in the UK
Cuthbert is not the only caterpillar cake on UK shelves. In fact, almost every major supermarket has its own version. Tesco’s Curly, Asda’s Clyde, Sainsbury’s Wiggles, and Waitrose’s Cecil are among the other supermarket caterpillar cakes. However, the original and most famous is Colin the Caterpillar, made by Marks and Spencer since 1990.
Why Colin the Caterpillar Matters to M&S
Marks and Spencer’s “Colin the Caterpillar” cake is a children’s birthday staple. More than 15 million Colin cakes have been sold since it was launched in 1990, and the caterpillar and its female version Connie have been turned into a wider range including cupcakes, trifles, sweets and chocolates. For M&S, Colin is not just a product. He is a brand icon. Furthermore, he is tied to the company’s partnership with cancer charity Macmillan Cancer Support, adding an emotional and charitable dimension to his public identity.
Why Did M&S Sue Aldi Over Cuthbert?
The legal battle that made Cuthbert famous began in April 2021. Understanding why M&S took action requires knowing what they were trying to protect.
The Trademark Claim
Marks and Spencer is taking legal action to defend a cake shaped like a caterpillar. The company makes a Colin the Caterpillar cake and claims Aldi is selling a copy caterpillar, Cuthbert. Both are made with sponge cake and chocolate, topped with colorful candies and a smiling, white chocolate face.
M&S has three trademarks relating to the cake, which the retailer believes means Colin has acquired and retains an enhanced distinctive character and reputation. In other words, M&S did not just own the recipe. It claimed to own the look, feel, and overall impression of the cake as a recognisable brand asset.
Riding on the Coat-Tails
Marks and Spencer went on to accuse Aldi of “riding on the coat-tails” of its reputation, and of misleading customers that the caterpillars are of the same standard. The argument was not just about copying. It was about confusion. M&S argued that customers seeing Cuthbert on an Aldi shelf might assume it was made to M&S standards, which they felt damaged the value of their premium brand.
Papers Filed at the High Court
Papers filed at the High Court on April 14 state that the design of the cake and its packaging, which closely resembles its Colin product, infringe its trademarks and call on its rival to desist from selling Cuthbert. The legal action asked for Aldi to remove Cuthbert from shelves entirely and to agree never to sell anything resembling Colin in the future. That was a bold request given that Aldi had been selling similar cakes since 2019 without any prior complaint.
Why Now?
One of the most-asked questions at the time was simple: why sue now? The most confusing aspect of this whole feud is why now? Cuthbert is not the first copycat caterpillar cake. Waitrose, Sainsbury’s, Tesco, Co-op, Morrisons and ASDA all have their own versions. The answer, many analysts suggested, was that M&S had grown tired of seeing its brand diluted across the market. Furthermore, Cuthbert had become more visible and more directly competitive than some of the others. That made it the natural target.
How Did Aldi Respond? The FreeCuthbert Campaign
What happened next is the part of the story that made Cuthbert famous well beyond the world of cake.
The Prison Box and the Social Media Blitz
As a response, Aldi changed Cuthbert’s box to include prison bars and showed him getting arrested in the 2021 advertisement. That single creative decision captured the public imagination immediately. The idea of a caterpillar cake being sent to prison was funny, absurd, and perfectly designed for social media sharing. Within hours, it was everywhere.
The FreeCuthbert Hashtag
Aldi used the hashtag to launch a viral social media campaign, mocking the legal action and gaining public support. The #FreeCuthbert hashtag trended across the UK, earning Aldi support from both consumers and the media. The hashtag was pure genius. It reframed the entire story. M&S went from being the wronged party protecting its intellectual property to looking like a powerful corporate giant bullying a budget rival over a children’s birthday cake.
Other Supermarkets Joined In
Even though Aldi made sure to tag its rivals in the tweet, Waitrose was the only one of them to directly respond to being dragged into the argument, admitting that “Cecil is watching.” With Waitrose signing up to the caterpillars for cancer movement, it seemed Colin may be left with no option but to join in. The whole UK supermarket industry got swept up in the joke. Furthermore, the public loved every minute of it.
Charity Fundraising as a Power Move
Aldi also brought back the controversial cake in stores (Cuthbert had actually been discontinued two months before M&S lodged a complaint) in order to raise money for Teenage Cancer Trust and the two retailers’ mutual charity partner, Macmillan Cancer Support. This move was brilliant for two reasons. First, it made Aldi look generous and community-minded. Second, it made it almost impossible for M&S to escalate the legal action without looking like it was standing against cancer charities. How could anyone sue a peace offering, charity-giving caterpillar?
The Public Verdict
The court of public opinion ruled firmly in Aldi’s favour. The social media buzz turned Cuthbert into a household name and framed M&S as the corporate giant picking on a more playful rival. The funny tweets collectively received hundreds of thousands of likes and were shared across multiple platforms. As a result, Aldi turned a potentially damaging legal story into one of the best free marketing campaigns in recent British retail history.
How Did the Legal Case End?
After months of legal proceedings, the case came to a close in early 2022.
The Confidential Settlement
Deputy Master Timothy John Bowles signed off an agreement in a consent order filed at the High Court, resolving the case. The order allowed the claim to be withdrawn and said that the warring retail giants had reached a “confidential agreement” on November 5.
The bitter legal dispute over the sweet treats began in April 2021, when M&S said Aldi’s version of its famous cake infringed its trademark as the similarity of the products would lead customers to believe they are of the same standard. After ten months of legal proceedings, the two companies settled privately. Neither side revealed the specific terms.
M&S Claimed Victory
An M&S spokesperson told Retail Gazette: “The objective of the claim was to protect the IP in our Colin the Caterpillar cake and we are very pleased with the outcome.” M&S was keen to frame the settlement as a win on its part.
A New Look
Aldi confirmed at the time that it was relaunching a limited edition Cuthbert the Caterpillar cake following the legal dispute. “Cuthbert is free and looking forward to seeing all his fans again very soon”, said an Aldi spokesperson.
The New Look Cuthbert
The redesigned Cuthbert kept his chocolate sponge identity but gained a distinctive bowtie and other visual changes that helped him stand apart from Colin more clearly. When Aldi brought its cake onto the market last year, it said that it had made many changes to Cuthbert’s face so that it did not resemble Colin the Caterpillar or cause confusion. Those changes were enough to satisfy the terms of the settlement and allow Cuthbert to keep his place on UK birthday tables.
Why Does Cuthbert Keep Coming Back Into the News?
The original lawsuit was settled in 2022. However, Cuthbert continues to trend and attract attention years later. There are several reasons for this.
New Products and Seasonal Editions
In November 2025, a new Cuthbert plush was released packaged with some apple gummy sweets shaped like Cuthbert’s head. Aldi has been smart about keeping Cuthbert relevant through regular new product launches and seasonal appearances. Each new release brings a fresh wave of social media attention and keeps the character in the public conversation.
Aldi’s Continued Use of Cuthbert in Advertising
Aldi has not been shy about using Cuthbert to poke fun at M&S in its advertising even after the settlement. In the advertising clip, Cuthbert the Caterpillar, Wiggles from Sainsbury’s cake, and Morris from Morrisons’ cake come face to face with Colin as price comparisons of products are shown on screen. It appears to be a reference to the 2021 lawsuit in which M&S filed a lawsuit against Aldi, accusing the German supermarket of copying its caterpillar cake design. That kind of continued humour keeps the story alive in the public mind.
A Story That Perfectly Captures the Mood
The Cuthbert story also keeps trending because it taps into something that British people find genuinely enjoyable. It is a story about a cake. It involves corporate lawyers, prison box designs, charity fundraising, and Twitter wars between supermarkets. Furthermore, it positions a scrappy budget retailer as the fun, clever underdog against a stuffy establishment brand. That narrative never gets old.
Lessons for Brands Everywhere
The case is now widely studied in marketing and legal circles as a textbook example of how to handle a brand crisis with humour and creativity. The case ended with a confidential settlement in 2022, and both parties agreed to withdraw the claim without disclosing details. However, the real outcome was that Aldi gained far more value from the publicity than M&S gained from the legal action. As a result, the story continues to be referenced every time a new brand dispute breaks out anywhere in the world.
Cuthbert vs Colin: A Full Comparison
| Feature | Cuthbert (Aldi) | Colin (M&S) |
|---|---|---|
| Launched | 2019 | 1990 |
| Price | £6.99 (625g) | More expensive premium pricing |
| Filling | Buttercream | Cream |
| Decoration | Colourful chocolate buttons, white chocolate face, bowtie | Colourful chocolate buttons, white chocolate face |
| Packaging | Redesigned after settlement (added bowtie) | Classic green box |
| Charity Link | Teenage Cancer Trust (limited editions) | Macmillan Cancer Support (ongoing) |
| Legal Status | Settled November 2021, publicly announced February 2022 | Trademark holder |
| Social Media Following | Gained huge following after FreeCuthbert campaign | Large established fanbase |
| Recent Activity | New plush product, November 2025 | Continues as M&S flagship product |
| Public Perception | Lovable underdog | Premium British icon |
Cuthbert the Caterpillar Full Attributes at a Glance
| Attribute | Details |
|---|---|
| Product Name | Cuthbert the Caterpillar |
| Made By | Aldi UK |
| Introduced | 2019 |
| Product Type | Chocolate sponge celebration cake |
| Price | £6.99 (625g) |
| Filling | Sweet buttercream |
| Coating | Chocolate |
| Decorations | Colourful chocolate buttons, cheerful white chocolate face, bowtie (post-settlement) |
| Key Rival | Colin the Caterpillar (M&S, launched 1990) |
| Other Caterpillar Rivals | Curly (Tesco), Clyde (Asda), Wiggles (Sainsbury’s), Cecil (Waitrose), Morris (Morrisons) |
| Legal Dispute Filed | April 14, 2021 at the High Court |
| Filed By | Marks and Spencer |
| Grounds for Lawsuit | Trademark infringement and passing off |
| Aldi’s Response | Prison bar packaging, FreeCuthbert hashtag campaign |
| Hashtag | #FreeCuthbert |
| Settlement Date | November 5, 2021 (confirmed publicly February 2022) |
| Settlement Type | Confidential agreement, both claims withdrawn |
| M&S Statement | “Very pleased with the outcome” |
| Aldi Statement | “Cuthbert is free and looking forward to seeing all his fans again very soon” |
| Post-Settlement Design | Added bowtie and other visual changes to differentiate from Colin |
| Current Status | Still on sale at Aldi with new look |
| Charity Editions | Yes, linked to Teenage Cancer Trust |
| Plush Product | Released November 2025, with apple gummy sweets |
| PR Outcome | Widely regarded as one of the best brand crisis responses in UK retail history |
| Colin Cakes Sold | Over 15 million since 1990 |
| Aldi Campaign Reach | Hundreds of thousands of likes and shares across platforms |
| Marketing Award | Referenced in business schools and PR courses as a case study |
| BBC Coverage | Yes, covered as a major news story in April 2021 |
| Why Still Trending | New products, Aldi ads referencing M&S, and strong ongoing public interest |
10 Frequently Asked Questions About Cuthbert the Caterpillar
What is Cuthbert the Caterpillar?
Cuthbert the Caterpillar is a chocolate sponge celebration cake sold by Aldi UK. It was introduced in 2019 and quickly became popular for its low price and fun design. The cake features a chocolate coating, buttercream filling, colourful chocolate button decorations, and a cheerful white chocolate face. After a 2021 trademark dispute with M&S, Cuthbert also gained a distinctive bowtie as part of his redesigned look. Furthermore, he has become one of the most recognisable characters in recent UK retail culture thanks to the viral story surrounding him.
Why did M&S sue Aldi over Cuthbert the Caterpillar?
M&S filed a trademark lawsuit against Aldi at the High Court in April 2021. The company claimed that Cuthbert the Caterpillar was too similar in design to its own Colin the Caterpillar cake, which M&S has sold since 1990. The lawsuit argued that the similarity between the two cakes could confuse customers and damage M&S’s premium brand reputation. Furthermore, M&S had three registered trademarks relating to the Colin cake, giving it a legal basis to challenge products it believed infringed on those rights.
What was the FreeCuthbert campaign?
The FreeCuthbert campaign was a viral social media response by Aldi following M&S’s lawsuit announcement. Aldi redesigned Cuthbert’s packaging to feature prison bars, showing the caterpillar getting arrested, and launched the hashtag FreeCuthbert across its social channels. The campaign was an immediate hit. It framed M&S as a powerful corporate bully targeting a fun budget rival’s birthday cake. As a result, the hashtag trended across the UK, earning Aldi enormous public sympathy and turning what could have been a brand crisis into a public relations triumph.
Did Aldi win the legal case against M&S?
The case never went to a full trial. Instead, both companies reached a confidential settlement in November 2021, which was publicly announced in February 2022. M&S claimed it was pleased with the outcome and that the goal of protecting its intellectual property had been achieved. Aldi, on the other hand, kept selling Cuthbert in a redesigned form with a new bowtie. Both sides kept the specific terms private. In terms of public opinion, however, most people agreed that Aldi came out of the situation looking much better than M&S did.
Is Cuthbert the Caterpillar still on sale?
Yes. Cuthbert the Caterpillar is still available at Aldi stores across the UK. After the settlement, Aldi redesigned the cake with a bowtie and other visual tweaks to help distinguish it from Colin the Caterpillar. The redesigned version has been well received. Furthermore, Aldi regularly releases limited edition seasonal and charity versions of Cuthbert, keeping the character fresh and relevant. In November 2025, a new Cuthbert plush toy was also released alongside apple gummy sweets shaped like his head.
What is the difference between Cuthbert and Colin the Caterpillar?
Both are chocolate sponge celebration cakes with similar designs. The key differences are price, brand positioning, and a few design details. Cuthbert retails at £6.99 and is Aldi’s budget-friendly version. Colin is M&S’s premium product with a higher price point and a longer history, having been sold since 1990. After the settlement, Cuthbert gained a bowtie as a distinguishing feature. Furthermore, Colin is tied to Macmillan Cancer Support through long-term charity work, while Cuthbert has supported Teenage Cancer Trust through limited edition releases.
Why does Cuthbert the Caterpillar keep trending?
Cuthbert keeps coming back into public conversation for several reasons. Aldi regularly releases new products, seasonal editions, and advertising featuring Cuthbert. In November 2025, a plush toy version was released, which attracted a fresh wave of attention. Additionally, the original story is so widely loved that any new development brings thousands of people back to it. Furthermore, Aldi has continued to use Cuthbert in ads that reference the M&S rivalry, which ensures the story never fully leaves the public consciousness.
What other supermarket caterpillar cakes are there in the UK?
The UK supermarket cake aisle has a whole family of caterpillar rivals. Tesco sells Curly the Caterpillar. Asda has Clyde. Sainsbury’s offers Wiggles. Waitrose sells Cecil. Morrisons has Morris. All of these cakes were already on sale before M&S’s lawsuit against Aldi in 2021. As a result, many people questioned at the time why M&S chose to go after Cuthbert specifically rather than any of the others. The most widely accepted answer is that Cuthbert had grown large enough in popularity to represent a genuine commercial threat.
What happened to Cuthbert’s charity work during the lawsuit?
During the legal dispute, Aldi brought back a limited edition Cuthbert cake to raise money for Teenage Cancer Trust and Macmillan Cancer Support. The charity move was both generous and clever. It made Cuthbert look like a positive force for good while making it very difficult for M&S to continue its legal attack without appearing to stand in the way of cancer fundraising. In other words, the charity element was a brilliant piece of PR that helped shift the public narrative further in Aldi’s favour.
What lessons did the Cuthbert case teach the retail and marketing industry?
The Cuthbert case taught the industry several important lessons. First, a strong and funny social media response can completely change the public narrative around a legal dispute. Second, using humour and creativity to reframe a crisis can turn a potential brand disaster into a major PR win. Third, charity partnerships can add a layer of public goodwill that is very difficult for rivals to attack. Furthermore, the case showed that smaller or budget brands can out-manoeuvre larger premium rivals in the court of public opinion even when they are on the back foot legally. As a result, the FreeCuthbert campaign is now studied in marketing and PR courses as one of the best examples of reactive brand communication in recent UK history.
Final Thoughts: Why Cuthbert the Caterpillar Keeps Trending
The story of Cuthbert the Caterpillar is really a story about two different ideas of what a brand can be. M&S believed that its 30-year investment in Colin the Caterpillar deserved legal protection. That is a fair and reasonable position. Colin is a genuine British institution, and protecting intellectual property is a legitimate business concern.
However, Aldi understood something that M&S perhaps did not. In 2021, the court that mattered most was not the High Court in London. It was the court of public opinion on Twitter and TikTok and Instagram. And in that court, a prison-barred caterpillar cake raising money for cancer charities was always going to beat a corporate legal letter.
Furthermore, Cuthbert keeps trending because his story is genuinely joyful. In a news cycle full of difficult and heavy stories, the idea of a chocolate caterpillar cake being sent to prison and then set free with a new bowtie is simply a lovely thing to read about. As a result, every new product, every new ad, and every anniversary of the original case brings fresh waves of people back to it.
In 2026, Cuthbert the Caterpillar is back on shelves, wearing his bowtie, and looking very much like a caterpillar who knows he won.