Introduction

Online choice architecture (OCA), often labelled “dark patterns” when harmful, has moved decisively from a behavioural economics concern to a core enforcement priority in both the EU and the UK.

If you are advertising, or providing goods and services online, to consumers in the UK and/or the EU you need to be aware of how these new rules are being enforced.

While earlier regulatory action relied largely on traditional consumer protection concepts of deception and unfairness, recent frameworks—most notably the EU Digital Services Act (DSA), the EU Digital Markets Act (DMA) and the UK Digital Markets, Competition and Consumers Act 2024 (DMCCA)—now enable direct scrutiny of the online interface design itself.

We have summarised below how enforcement and regulatory action has been taken against dark patterns choice architecture, based on the three Acts mentioned above, by reference to the types of online commercial practice which have been the subject of enforcement actions.

Sludge, Roach Motels and Exit Friction

One of the clearest areas of enforcement concerns “sludge”: online design practices that make it harder for a consumer to refuse, exit or cancel a service than it was to sign up initially.

At EU level, Article 25(1) DSA prohibits interface design that “materially distorts or impairs” users’ ability to make free and informed decisions, while Article 25(3)(c) explicitly highlights making termination more difficult than subscription as a suspect practice which would fall within the ambit of Article 25(1) DSA (Regulation (EU) 2022/2065, Art 25).

In the UK, this typology has already translated into concrete enforcement. The CMA’s investigations into online mattress retailers and Wowcher (undertakings accepted July 2024) focused on cancellation friction and pressure tactics, including misleading timers and obstructive flows. These cases now sit squarely within the DMCCA’s reformed unfair commercial practices regime, under which the CMA can impose administrative fines of up to 10% of global turnover (Digital Markets, Competition and Consumers Act 2024, Part 4).

Regulatory signal: Exit friction is treated as a high‑certainty infringement, with settled expectations on symmetry between entry and exit.

False Urgency and Scarcity Claims

Another commercial practice which now been has a strong enforcement track record against it is the practice of manufactured urgency or scarcity, such as the use of countdown timers or “only X amount left” claims, that are not in fact grounded in reality.

In the UK, the CMA has repeatedly targeted such practices since 2022, with notable investigations by the CMA into Simba Sleep, Wowcher, and Emma Group. This culminated in the CMA issuing formal detailed guidance on reference pricing and urgency claims in August 2024. These cases are now low‑ambiguity enforcement targets under the DMCCA, requiring no novel legal theory beyond the demonstration that the claim was misleading.

At EU level, the same conduct can fall within Article 25(1) DSA where urgency cues manipulate decision‑making, even if they might also be addressed under the Unfair Commercial Practices Directive (see recital 67 DSA). The DSA thus adds an autonomy‑based lens, enabling regulators to focus on the effect of urgency design rather than only its factual accuracy.

Regulatory signal: False urgency is easy to evidence and increasingly treated as a per se high‑risk OCA commercial practice.

Unequal Choice Prominence, Defaults and Steering

Choice steering through defaults, layout or prominence is a point of convergence between competition law and consumer regulation.

Under the DMA, obligations imposed on designated gatekeepers restrict the use of defaults and interface design that undermines user choice or entrenches market power (e.g. Regulation (EU) 2022/1925, Arts 5(2), 6(3), 6(11)). Although DMA enforcement to date has been framed in competition terms, the same interface conduct can simultaneously engage Article 25 DSA where it impairs autonomous decision‑making.

In the UK, the CMA has treated biased choice architecture as a form of misleading or aggressive practice, building on the taxonomy developed in its Online Choice Architecture discussion paper (CMA155, 2022). Under the DMCCA, this analysis now has direct enforcement consequences, without the need to litigate through the courts.

Regulatory signal: Dual exposure is emerging—one interface can trigger the application of both competition law and consumer protection remedies.

Confirm‑Shaming and Emotional Manipulation

Confirm‑shaming—using guilt‑inducing language to discourage refusal—is less established in case law but increasingly prominent in regulatory analysis.

The DSA explicitly recognises emotional manipulation as a threat to autonomous choice in Recital 67, even where no objectively false statement is made. This marks a significant evolution from classical consumer law. In the UK, similar conduct is likely to be characterised as an aggressive practice under the DMCCA, particularly where it exploits consumer vulnerability or exerts undue pressure.

While enforcement remains emergent rather than settled, academic commentary and Commission guidance indicate declining tolerance for emotionally coercive interface design.

Regulatory signal: This is a growing risk area, with the protection of consumer autonomy rather than deception as the primary hook.

Drip Pricing and Hidden Costs

Drip pricing, where unavoidable charges are revealed late in the transaction, is now a black‑letter enforcement issue in the UK, and one on which the CMA has issued exhaustive guidance. The DMCCA expressly bans such practices as unfair commercial conduct, reflecting long‑standing CMA priorities.

In the EU, drip pricing is more commonly addressed via the Unfair Commercial Practices Directive, but can still be relevant to DSA assessments where presentation and timing of information distort decision‑making.

Regulatory signal: In the UK, this is a mature and high‑certainty enforcement category.

Conclusion

Across the EU and UK, enforcement practice demonstrates a clear pattern: regulators are no longer interested solely in what information is provided, but how choices are structured and experienced. Online commercial practices such as sludge, false urgency, biased defaults and hidden costs are already the bread and butter of regulatory enforcement activities, while emotional manipulation and confirm‑shaming are rapidly moving into scope. The combined effect of the DSA, DMA and DMCCA is to make interface design itself a regulated activity, with significant financial and reputational consequences for non‑compliance.

We have summarised in the table below how under each Act the different dark choice commercial practices are regulated:

 

Dark‑pattern typology	Description	EU DSA	EU DMA	UK DMCCA
Sludge / friction	Making exit, cancellation or refusal harder than entry	Art 25(1); Art 25(3)(c) DSA	(indirect: only If used to entrench gatekeeper power)	Unfair commercial practices (obstruction)
Confirm‑shaming	Guilt‑inducing language to steer choices	Art 25(1); Recital 67	❌	Likely “aggressive” or misleading practice
Unequal choice prominence	Visual or structural bias toward preferred option	Art 25(3)(a)	Defaults / self‑preferencing constraints	CMA OCA enforcement
Nagging / repeated prompts	Repeatedly asking after refusal	Art 25(3)(b)	❌	Aggressive practice
Pre‑selected defaults	Opt‑outs rather than opt‑ins	Art 25(1); Recital 67: Autonomy impairment	Art 5(2), Art 6 DMA	Unfair practices
False urgency / scarcity	Countdown timers, “only 2 left” claims	Art 25(1) Manipulation of decisions	❌	Misleading practice
Roach motel	Easy sign‑up, hard exit	Art 25(3)(c); Recital 67: Explicitly flagged	❌	Subscription /obstruction focus
Drip pricing	Incremental disclosure of unavoidable costs	Indirectly dealt with via UCPD carve‑out	❌	Explicitly banned practice
Disguised ads	Ads presented as neutral UI	Art 26 and 28; Recital 68: DSA ads transparency	❌	Misleading practice

If you would like to discuss how these developments affect your online business or digital compliance strategy, Daniel Lloyd would be pleased to hear from you.