Labelling Authorities

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Labelling Authorities
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About Quatro

Labelling Authorities

The Quatro system is designed to make trustmarks, quality seals and other content labels more valuable to scheme operators, more attractive to service providers and more visible to end users. Quatro can be added to an existing trust mark or labelling scheme without any need to reengineer existing infrastructure or change the assessment criteria used.

The basic concept is that, in addition to any graphic, the Labelling Authority (LA) issues its clients with a machine-readable label that encodes the various assertions made by the LA about the website in question. For example, a label may include an assertion that the labelled website has a suitable privacy policy, that the publisher is clearly identified, and that it meets legal practice in one or more identified countries. Whilst it is possible to include a coarse-grained statement that “this website has the Seal of Approval,” the granular data is important for the interoperability and independence of labels offered by different LAs.

Labelling Authorities distinguish themselves from one another by a variety of means, including the criteria they use in deciding whether or not to award their trustmark. Recognising this, use of Quatro does not mandate that all LAs switch to a common set of criteria. However, there are a relatively small number of criteria that, research showsi , are highly likely to be used by any LA, no matter what their particular area of concern may be. These elements are collected in the Quatro Vocabulary. Where an LA’s criteria exactly or closely match those defined in the Quatro descriptors, the latter should be used. Where there is no match, the LA will derive its own descriptors from its own assessment criteria. A typical label will therefore include descriptors from both the Quatro vocabulary and the LA’s own vocabulary.

If a machine that can recognise the labels issued by one Labelling Authority finds a label issued by another, it may not be able to make direct use of the data specific to the label authority it has detected. However, the elements from the Quatro vocabulary will be understood by all participants. Thus, each LA benefits from the common system without any loss of its own distinguishing features and commercial interests.

Full details of how Labelling Authorities can participate in Quatro are given in a separate document: How to make your trustmark machine-readable

i The UNICE – BEUC e-Confidence project. The final report, published 22/10/01 is available from but is more easily found at