Note: This advice is given by the CAP Executive about non-broadcast advertising. It does not constitute legal advice. It does not bind CAP, CAP advisory panels or the Advertising Standards Authority.


Superlative claims are those which claim that something is superior to all others, whether it is a broad superlative claim, such as “the best” or a specific superlative claim, such as “the most customers” or “the highest rated”. Superlative claims can be either subjective or objective. Claims which are clearly subjective do not usually need to be supported by evidence, however all objective claims must be.

Objective superlative claims

As with all comparative claims, superlative claims must be presented in a way which is unlikely to mislead, and the advertiser must hold evidence which supports the claim.

“Biggest”, “best-selling”, “leading” and other similar claims are generally treated as objective best-selling claims that require evidence of highest sales or highest market share. Depending on the context of the claim and on readers’ likely interpretation of the claim, the ASA might be satisfied with a sterling (£) justification or a unit justification for the claim; if the intended basis of the claim is unclear to the addressed audience, marketers should hold evidence of both or the ad should explain the intended basis. The evidence needs to relate to the subject of the claim, and to a long enough period (usually a year) to constitute a genuine sales advantage and not reflect merely a brief surge in sales. In the housing market, the ASA and CAP do not accept a count of “For Sale” boards as evidence of a market-leading position because not all vendors have a board outside their home (Blakes Estate Agents, May 1999).

An ad which made the claims “the leading trademark registration service” and “the leading online trademark registration service” was ruled misleading by the ASA, who considered that consumers would understand the claims to mean that the advertiser had registered more trademarks than any other business and any other online business. Because the advertisers did not have evidence to demonstrate that this was the case, complaints about the ad were upheld (Trademark Eagle Ltd, 21 February 2018). See also LittleLamb Ltd, 11 February 2015 for ‘best-selling’, and Challs International Ltd, 17 February 2016 for ‘No. 1’.

Best claims can be qualified or unqualified, and the likely interpretation of an unqualified best claim will depend on the product or service advertised and the context in which the claim appears. In 2018 the ASA upheld a complaint about an ad which stated that the advertiser’s mobile phones were the “best value”. In this case the ASA considered that consumers would interpret the claim “The UK’s best value mobile” to relate to the features integral to the nature of a mobile phone service: minutes, texts and data, and because the advertiser did not offer more data, minutes and texts than all other UK mobile tariffs relative to the costs of the tariffs, found the claim misleading (Utility Warehouse Ltd, 08 August 2018). See also The Carphone Warehouse Ltd, 03 August 2016.

When making comparative claims, as well as holding evidence to support the claim advertisers must ensure that they are clear, supported by evidence, compare products or services intended for the same purpose, and are verifiable (3.33 – 3.40). See Comparisons: GeneralComparisons: Identifiable competitorsComparisons: Verifiability.

Marketers should note that superlative claims which are based on the outcome of a consumer survey, for example 99% of customers said X product was the best”, are likely to be considered objective claims about the results of the survey, and would need to be supported by evidence. See Substantiation: Consumer surveys and sample claims.

Subjective superlative claims

Sometimes superlative claims are clearly subjective claims which are likely to be understood as matters of opinion. For example “the most enjoyable car buying experience you’ll ever have!” (Stoneacre Motor Group car dealers, 11 September 2002), “friendliest nursery” and “Nowhere else makes you feel this good”.

If the basis of a claim is unstated, and is unclear from the rest of the advertisement, the ASA may regard the claim as the subjective. The ASA investigated an ad which stated “10/10, is this the best vacuum cleaner ever?”, and considered that the claim was clearly an expression of opinion posed as a question, rather than an objective claim. However, the ad was considered misleading because it did not make it clear who had given the quote, or when it was given, which was information needed by consumers to understand the context from which it came (Grey Technology Ltd, 20 April 2016).  However, this is not always the case, and in 2018 the ASA considered the claim “best available tickets” without a qualification was considered an objective claim. The ASA considered that consumers were likely to interpret the claim "the best available tickets" to mean that those tickets were better than any other available tickets for the event generally. Whilst they appreciated that what was considered "best" depended on the genre of the event, and to some extent, individual preferences, they considered consumers were likely to view "the best available tickets" in the context of the ad to mean that those tickets offered a tangible benefit compared to other tickets on sale and were therefore better than all the other tickets available for the event, because, for example, they were closer to the stage, or offered a better view of the stage. Because Ticketmaster did not have evidence to demonstrate that this was the case, the claim was considered misleading (Ticketmaster UK Ltd, 03 January 2018).

However marketers should be cautious when using subjective claims or stating matters of opinion and should ensure that these will not mislead; marketing communications must not imply that expressions of opinion are objective claims (Code rule 3.6). Even if a claim is subjective, the claim must not mislead. In 2005 the ASA upheld a complaint about the claim “the ultimate broadband experience”. Although it accepted the claim was the advertiser’s opinion, the ASA considered the incidence of severe customer dissatisfaction with the service was enough to make the claim misleading (Bulldog Communications Ltd, 2 March 2005).

Code rule 3.2 states that obvious exaggerations ("puffery") and claims that the average consumer who sees the marketing communication is unlikely to take literally are allowed provided they do not materially mislead. In 2013, the ASA ruled that the claims "to achieve the unachievable" and "Comfort redefined" in trade magazine ads for a contact lens brand would be understood as puffery, rather than objective claims based on evidence (Alcon Eye Care UK Ltd, 4 September 2013).


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