According to the firm, proposed changes to the 2002 European Communities Directive on Privacy and Electronic Communications would make it so that in future, websites would only be able to place cookies on visitors’ computers if they give their express consent.

Concerns centre on an amendment to article 5 ( 3 ) which states:

“Member States shall ensure that the storing of information, or the gaining of access to information already stored, in the terminal equipment of a subscriber or user is only allowed on condition that the subscriber or user concerned has given his/her consent, having been provided with clear and comprehensive information, in accordance with Directive 95/46/EC, inter alia about the purposes of the processing.”

The amendment does not prevent storage and access to information that is “strictly necessary” in order to provide a service explicitly requested by a website subscriber or user.

However, it seems unlikely that tracking visitor behaviour or the success of ad campaigns will be deemed to be “strictly necessary” for the provision of all web-based services, says Andrew Girdwood, Bigmouthmedia’s head of search.

A paid-for website like the Financial Times, for instance, could argue that cookies are necessary to authenticate users and facilitate the sign-in process, but those sites providing free content might struggle to justify their use of the technology without consent being given.

Girdwood said: “This is a proposal that would strike at the very heart of what the digital economy is all about. The ability to measure, track and improve the site experience for visitors is key to the success of e-commerce, and given the potentially damaging effect this could have on a multi-billion pound business channel, it suggests legislators don’t quite appreciate the havoc they could cause.”

Click here to read Girdwood’s detailed case against the proposed amendment.