This page lists cookies in use on the IWM's main website. Read more about how and why we use cookies on this site and how to control them, and see here for cookies used on our other websites.

First Party Cookies Set by IWM Software

  • has_js.  Session duration. Allows the server to know if it can depend upon javascript. Set to "1" if user has javascript enabled by whichever page a visitor arrives on
  • session id. 3 weeks duration. Used to log in. Set on any page when a visitor arrives
  • cookiesenabled. 1 year duration. Used to decide whether to show the "cookie warning" bar. If this cannot be set to true then cookies are disabled and the bar is not shown. Set on any page when a visitor arrives
  • cookieconsent. 6 month duration. Set if the visitor has dismissed the "cookie warning" bar and thus indicated that they do not need to be warned again. Set on any page when a visitor dismisses the bar

First Party Cookies Set for Other Services

Google Analytics

  • __utma
  • __utmb
  • __utmc
  • __utmz
  • ___utmv
  • All of the above: Various duration: a mix of session and "permanent" cookies lasting 30 mins, 6 months, or 1-2 yrs. Anonymously tracks use of website.  These cookies are set or updated on any page visited. See here for full details. Several cookies are set but all serve the same purpose: to see how people reached the site and used it, including search terms used and referring sites.


  • optimizelyEndUserId
  • optimizelyBuckets
  • optimizelySegments
  • optimizelyRedirect
  • optimizelyPendingLogEvents

Optimizely is a A/B testing tool. The cookies hold short alphanumeric string values to store page variant and experiment data. The cookies do not store any personally identifiable information.

Hot Jar

  • _hjIncludedInSample
  • _hjMinimizedPolls
  • _hjUserId
  • _hjDonePolls

Hotjar is an analytics and feedback tool that we use to understand how our website is used and improve usability. Hotjar sets cookies to help us track behaviour across pages and to control visitor polls. The cookies carry no personally identifiable information.


  • sv893-[XXX].  Various duration from 1 day to 1 year. Used to see how people interact with our pages
    Up to four cookies starting "sv893-" are set by Reinvigorate and containing numbers like "18764627". Set on any page when a visitor arrives. Reinvigorate gives us insights into what people do on our web pages - which buttons they click etc - so we can improve our design.

Third Party Cookies

  • Quantcast. Duration: 18 months. Our pixel is used for anonymous audience measurement (no PII) and targeted display advertising (a.k.a online behavioural advertising)
  • Sizmek. Activityino2, targetinginfo, u2. Duration: 4 months. Sizmek cookies allow us to assess the effectiveness of our banner adverts and ensure we do not expose you to the same advert multiple times.  It contains no personal or sensitive information. The tag can also be used for ROI.
  • Google Translate ( PREF. This cookie is associated with the use of the Google Translate widget on our pages
  • AddThis.__atuvc, Uit, Ssh, Sshs, Ssc, Uid, Uvc, psc. Duration: 1 month - 2 years. Track usage of AddThis links. The cookies may be set and used on other websites too. AddThis explain their cookies (anonymous tracking cookies) here and offer an opt-out mechanism here. Clearspring, the company the provides AddThis, owns some other companies and domains connected to advertising. Their cookies have not been observed on our site but include and
  • Vimeo. __utma, __utmb, __utmc, __utmz.  Cookies for tracking use of embedded videos. They appear to be Google Analytics cookies but set by Vimeo. They are only set when movie loads. We can't show videos without them. See
  • Vimeo for comScore. Tied in to Vimeo player. comScore, the company behind this cookie, reports on the use of websites across the internet. More information here
  • Facebook. Duration: 180 days. We use the Facebook Pixel to understand conversion tracking, for optimisation and remarketing purposes. For information on how to opt out visit:!/. To view Facebook’s privacy policy visit:
  • AdYouLike. Duration: 13 months. Webpage visitors are tagged with cookies placed in your browser to provide personal advertising based on recent browsing. No IP address or personal data information is collected. For info, to opt out and to view AdYouLike’s privacy policy visit:
  • Videology. Duration: Up to 1 year. For info, to opt out visit. Videology collects data and ad decisioning to optimise performance of video and display advertising campaigns. To view Videology’s privacy policy visit:
  • Teads. Duration: Up to 1 year. Teads use cookies to prevent visitors seeing repeat adverts and to make more relevant. To view Teads’ privacy policy visit:   
  • Captify. Captify collects Non-Personally Identifiably Information (N-PII) via anonymous cookies placed on our partners’ websites or through mobile advertising identifiers within partners’ mobile applications to provide more personalised advertising. To view their privacy policy visit:

IWM Website Cookie List version 5, 2017-08-01