Summary
- A cookie can last 7,984 years, according to new international privacy study.
- UK websites place more cookies but give more information than any other country surveyed.
Original Author: ICO
Original Link: https://ico.org.uk/about-the-ico/news-and-events/news-and-blogs/2015/02/a-cookie-can-last-7984-years-according-to-new-study/
Content
An international study led by the UK’s Information Commissioner’s Office (ICO) into the use of cookies has revealed that some websites are placing cookies on computers and other devices that will long outlast the usefulness of the device.
A cookie is a small file of letters and numbers that is stored on a device when it is used to visit a website. Cookies are used by many websites and can do a number of things, eg remembering your preferences, recording what you have put in your shopping basket, and counting the number of people looking at a website. Some cookies, known as third party cookies, can also be used to record information based on how the user is interacting with other websites.
The study involved an automated and manual examination of 478 websites by eight privacy regulators from the European Article 29 Working Party and other national regulators who have responsibility for enforcing the rules on cookies.
The key findings from the research are:
The websites surveyed set a total of 16,555 cookies.
The average website placed 34 cookies on a device during a person’s first visit. UK websites placed an average of 44 cookies on a first visit, the highest of any country surveyed.
70% were third party cookies (set by websites other than the one being visited). 30% of cookies set were first party cookies (set by the site being visited).
86% of cookies were persistent cookies (remain on a person’s device after use). 14% were session cookies (removed after a person’s browsing session has ended).
The average cookie is set to expire after one to two years but some cookies were being set for as long at 10, 100 or even nearly 8000 years.
31st December 9999. Cookies set by three websites would not expire until 9999. One of these websites was based in the UK.
The use of cookies in the UK is governed by the Privacy and Electronic Communications Regulations (PECR). The regulations require organisations to provide clear information about how cookies are used on their website and allow people to make a real choice about whether they are happy for non-essential cookies to be placed on their device.
In the UK, 94% of the 81 websites surveyed provided information to explain to visitors how cookies were being used on the site. This compares favourably when compared to elsewhere across Europe where only 74% of the websites surveyed provided any information about cookies.
The most common method of informing visitors about the use of cookies was by using a banner at the top of a webpage. This approach was used by 59% of the websites surveyed where information was provided. Just over 39% used a link to further information about cookies in the header or footer of a webpage.