The UK cookie law / EU cookie directive, also known as the EU e-Privacy Directive, is more formally known as the “UK Privacy and Electronic Communications Regulation”
It became effective in the UK on 26th May 2012.
That’s the date when the Information Commissioner’s Office (ICO) was due to begin enforcing the new rules.
Who does it apply to?
All websites that use cookies which may be delivered to devices being used in the UK or EU countries.
Further reading
UK law
Privacy notices