> Quantcast Measure cookies, audience segments and US data transfers, and how to deploy the Quantcast pixel on European sites with valid GDPR consent. > > Canonical: https://www.flowconsent.com/en/services/analytics/quantcast-measure Analytics # Quantcast Measure Analytics Quantcast Measure is a free audience measurement and advertising analytics service operated by Quantcast (San Francisco). The product places a JavaScript pixel and cookies on publisher and advertiser sites to count unique visitors, build cross site audience segments and feed the Quantcast advertising platform. Because data is shared with the Quantcast advertising stack and replicated to the United States, Quantcast Measure is treated as a high risk advertising tracker under the GDPR and the ePrivacy Directive. [Block Quantcast Measure until consent](https://app.flowconsent.com/auth/sign-up?utm_source=flowconsent.com\&utm_medium=referral\&utm_campaign=analytics) · [Scan my site](https://www.flowconsent.com/en/scan) At a glance - Category [Analytics](https://www.flowconsent.com/en/services/analytics) - Consent Analytics - Prior consent Required - Documented cookies 4 - Third-party domains 4 - Servers Quantcast operates data centres in the United States, Ireland and Singapore. EU traffic is mainly processed in Ireland, but data is replicated globally and accessible from the US headquarters. Overview ## What does Quantcast Measure do? ## **What Quantcast Measure is** Quantcast Measure is the free audience measurement product offered by Quantcast. A JavaScript tag (quantserve.com) is added to every page of the site. The tag drops cookies, hashes user signals and reports impressions and visits to Quantcast servers, where the data is enriched with cross site behavioural data already collected on other sites in the Quantcast network. ## **Cookies and identifiers** Quantcast sets the third party advertising cookies mc, KRTBCOOKIE\_ and d, plus the first party \_\_qca cookie used by the publisher to identify a unique browser. These identifiers persist for up to 13 months, are synced with DSPs and SSPs through the IAB TCF, and feed the Quantcast Choice CMP and the Q for Publishers monetisation suite when those products are also deployed. ## **GDPR and ePrivacy implications** The cookies fall under Article 5(3) of the ePrivacy Directive, which requires prior consent. The audience profiling activity falls under Article 6(1)(a) GDPR. Because Quantcast Measure is integrated with the Quantcast advertising stack and the IAB TCF chain, legitimate interest is not an admissible legal basis: regulators consistently reject it for cross site advertising profiling. ## **Consent requirements** Quantcast Measure must only load after explicit, granular, opt in consent. Visitors must be able to refuse with the same effort as accepting, change their mind at any time and have their preferences honoured by the IAB TCF signal forwarded to downstream vendors. The service cannot run on consent assumed from continued browsing or scrolling. ## **International data transfers** Quantcast is headquartered in San Francisco. Personal data is transferred to the United States. Transfers rely on Quantcast self certification under the EU/US Data Privacy Framework and on Standard Contractual Clauses. Despite the DPF adequacy decision, controllers must run a transfer impact assessment given Quantcast US exposure to FISA 702 access requests. ## **Practical compliance steps** Block the Quantcast tag until consent is granted, configure your CMP to forward the IAB TCF string with Quantcast vendor ID 11, sign the Quantcast DPA and store the DPF certification reference, document the transfer impact assessment, list Quantcast Measure in the privacy and cookie policies and review the configuration after each TCF update. Compliance ## Quantcast Measure and the GDPR Quantcast Measure is classified as “Analytics”. On a site that targets European visitors, it must only load after the visitor consents, and it must be listed in your cookie policy. - Legal basis Article 6(1)(a) GDPR (consent) for the storage of identifiers and the audience measurement and advertising profiling carried out by Quantcast, plus Article 5(3) ePrivacy Directive for the cookies. Legitimate interest is not admissible because Quantcast performs cross site profiling and shares data with third parties through the IAB TCF. - Risk level high - Applicable regulations GDPR, ePrivacy Directive, IAB TCF v2.2, French CNIL guidelines, German TTDSG, Spanish LSSI, Italian Garante guidelines, UK PECR ### Impact assessment (DPIA) A DPIA is recommended for Quantcast Measure because of cross site behavioural profiling, persistent identifiers, integration with the Quantcast advertising platform and systematic transfer of personal data to the United States. The DPIA must include the IAB TCF chain of vendors that may receive Quantcast signals. ### Sample text for your banner > We use Quantcast Measure to count visitors and understand how our content is consumed across the web. Quantcast sets advertising cookies, builds audience segments and transfers data to the United States. We only load Quantcast after you click Accept. You can withdraw your consent at any time from the cookie settings. Cookies and trackers ## What Quantcast Measure sets and contacts - Tracking method JavaScript pixel (quantserve.com), third party advertising and audience measurement cookies, cross site identity stitching, IAB TCF v2.2 vendor (ID 11), cookie syncing with DSPs, fingerprinting signals (user agent, screen, language) and audience segments shared with the Quantcast Choice CMP and Q for Publishers monetisation suite. - Server location Quantcast operates data centres in the United States, Ireland and Singapore. EU traffic is mainly processed in Ireland, but data is replicated globally and accessible from the US headquarters. - Data transferred outside the EU Personal data is transferred to the United States. Quantcast relies on the EU/US Data Privacy Framework certification, Standard Contractual Clauses and a published transfer impact assessment. The pixel and cookies routinely send hashed identifiers, IP and behavioural signals to US servers. ### Cookies set (4) | Name | Type | Duration | Purpose | | ------------ | ---------- | --------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------- | | mc | persistent | 13 months | Quantcast advertising cookie used to identify and track unique browsers across the Quantcast network for audience segmentation and IAB TCF cookie syncing. | | d | persistent | 3 months | Quantcast measurement cookie that stores recent activity and frequency data for cross site audience analysis. | | KRTBCOOKIE\_ | persistent | 13 months | Quantcast/PubMatic cookie sync identifier used in real time bidding to match browsers between SSPs and DSPs. | | \_\_qca | persistent | 13 months | First party cookie set on the publisher domain to identify a unique browser within the Quantcast Measure visitor count. | ### Third-party domains contacted (4) - `quantserve.com` - `quantcast.com` - `quantcount.com` - `rules.quantcount.com` Questions ## Frequently asked questions about Quantcast Measure Can't find your question? Write to us, we answer fast. [Write to us](https://www.flowconsent.com/en/demo) ### What cookies does Quantcast Measure set? Quantcast Measure sets the third party advertising cookies mc, KRTBCOOKIE\_ and d on quantserve.com, plus the first party \_\_qca cookie. They persist for up to 13 months, are used to identify unique browsers and to sync with DSPs through the IAB TCF. ### Do I need consent to use Quantcast Measure? Yes. The cookies fall under Article 5(3) ePrivacy and the cross site profiling falls under Article 6(1)(a) GDPR. Quantcast Measure must be blocked until the visitor has given explicit, granular opt in consent through your CMP. ### What is the legal basis for Quantcast Measure? Consent (Art. 6(1)(a) GDPR) is the only admissible basis because Quantcast performs cross site behavioural profiling and shares signals with the IAB TCF chain. Legitimate interest is not acceptable. ### Does Quantcast Measure transfer data to the US? Yes. Quantcast is headquartered in San Francisco. Personal data is replicated to US data centres. Transfers rely on the EU/US Data Privacy Framework certification and Standard Contractual Clauses, and require a transfer impact assessment given FISA 702 exposure. ### Do I need a DPIA for Quantcast Measure? Yes. The combination of large scale cross site profiling, persistent identifiers, IAB TCF participation and US transfers triggers the DPIA criteria under WP248 and the EDPB threshold guidance. ### How do I implement Quantcast Measure compliantly? Tag block Quantcast until consent, integrate the CMP IAB TCF v2.2 string with vendor ID 11, sign the Quantcast DPA, store the DPF certification record, document a transfer impact assessment and refresh consent at least every 13 months. ### What are the alternatives to Quantcast Measure? Privacy first audience measurement alternatives include Matomo (self hosted in cookieless mode), Plausible, Fathom, AT Internet/Piano Analytics (EU based), Etracker (Germany) and Comscore Direct in the limited cases where consent is collected. None of these match the cross site reach of Quantcast, but they remove the IAB TCF and US transfer issues. ### How do I update the cookie policy for Quantcast Measure? List Quantcast Measure with the publisher (Quantcast International Limited, Ireland), the controller relationship (joint controller for IAB TCF), the cookies (mc, KRTBCOOKIE\_, d, \_\_qca) with retention up to 13 months, the legal basis (consent), the IAB TCF vendor ID (11), the transfer destination (United States) and the safeguards (DPF, SCC, TIA). 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