- 22 Oct 2024
- •
- 2 min read
What are dark patterns and online choice architecture?

Dark patterns and online choice architecture (OCA) have become increasingly relevant in legal and compliance discussions, particularly in relation to data protection, competition law and consumer law.
Whilst the legal frameworks for dark patterns and OCA vary depending on the context (UK GDPR/ PECR for data protection and The Consumer Protection from Unfair Trading Regulations 2008 and soon the Digital Markets, Competition and Consumers Act 2024 (DMCC) for competition/consumer law), the common concern is the negative impact on data subjects or consumers.
What do the terms mean?
The terms “dark patterns” and “OCA” are often used interchangeably, with OCA being the more commonly used term in the UK, especially by the Competition and Markets Authority (CMA). OCA refers to how websites and apps are designed to influence user behaviour. While OCA isn’t inherently negative, it becomes problematic when it distorts consumer decisions or affects competition.
Examples of problematic OCA
There are a number of examples of OCA that can negatively impact users. Here are some topical scenarios:
- Cookie consent: uneven options. A common example in a data protection context relates to cookie banners. Often, users are encouraged to accept cookies through one simple click, while rejecting cookies requires more time and effort with multiple steps. Another tactic is to visually emphasise the preferred choice of the website operator, such as:
ACCEPT ALL COOKIES – Reject all cookies
Many website users have also likely encountered a cookie banner that cannot be minimised without clicking a button – usually the most predominant being “accept all”.
- Manipulative language. OCA can use manipulative language to sway decisions. For example, a website might offer a discount for signing up for a newsletter, with options like ‘Yes please, take me to the savings’ and ‘No, I don’t want to save money’. This makes it difficult for website users to feel comfortable in declining the offer.
- False urgency or scarcity. The CMA has recently taken action against companies that create a false sense of urgency or scarcity. Statements like “1,000 people have bought this in the last hour” or “Only 1 left, hurry” often play on the fear of missing out. If these claims are misleading or untrue, they can distort consumer behaviour.
- Hidden subscriptions. A growing issue is consumers purchasing products or services on-line without realising they are signing up to a subscription. While it may be easy to sign up for these subscriptions, cancelling them can be difficult or unclear. The DMCC plans to address subscription traps, though the introduction of these new rules has been delayed until at least 2026.
Understanding these tactics can help professionals in legal and compliance roles navigate the complexities of online user experience and ensure their practices align with evolving regulations.

Disclaimer
This information is intended for general informational purposes only and does not constitute legal advice. We recommend seeking professional advice before taking any action on the information provided. If you would like to discuss your specific circumstances, please feel free to contact us on 0800 2800 421.