Digital Publishing Top Stories
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CMPs for publishers: a comparison guide

We’re only a few months into GDPR with many publishers still struggling with GDPR compliance and falling short of their obligations. Others, notably US publishers such as the Chicago Tribune and LA Times, are sidestepping the issue altogether and continuing to block European visitors.

What is clear is that the stringent requirements of GDPR have made things much more complicated for publishers, especially those working with multiple ad tech partners and who now need to obtain user consent for each one.

CMPs to the rescue

Whilst the current state of affairs with GDPR is causing both panic and technological innovation, a new solution – the Consent Management Platform (CMP) – is helping to simplify the current ‘compliance quagmire’ in the ad tech ecosystem. CMPs are an IAB-led initiative with the trade body putting the framework together alongside input from its member ad tech companies.

According to GDPR guidelines, publishers must ‘unambiguously’ get user consent for collecting, processing and using personal data. Due to the complexity of the online ad ecosystem, without the use of a CMP, getting such permissions is either nigh on impossible or, to comply, a publisher may have to take a significant revenue cut in terms of digital ad revenue.

This is why the CMP has become the unrivalled tool of choice for publishers compliance, with a significant percentage of the top 200 UK Alexa URLs choosing an IAB-approved CMP. Furthermore, with Google confirming that they will also endorse and join the framework by August, this number is expected to rise dramatically.

“Choice and transparency are important, and the industry needs to embrace these kinds of moves,” Damian Routleyan advisor at UnveilMedia recently told Econsultancy, adding,

Going forward, consent management platforms will be an essential part of programmatic strategy, if publishers want to benefit from revenue.

CMPs for publishers: which one to choose?

The key issue is which CMP should a publisher choose? The question is further complicated by the fact that both free-versions and paid-for versions are available.

A recent study looked at free and paid for CMPs found across the top 200 UK Alexa sites (excluding CMPs that are publisher-specific or are not IAB supported) and rated each one against a top 10 feature set, defined based on conversations with publishers in the UK and US.

Here’s a snapshot of the study:

A. There are 113 IAB registered CMPs available in the market:

* Out of these, 29 are publisher specific CMPs.

* Of the remaining 84, roughly half are free and half are paid for CMPs.

B. Free CMPs for publishers

Why is this technology being offered for free by some companies?

* To help publishers who might have otherwise struggled to comply with GDPR due to a lack of available resources.

* To improve the user experience of consent across the industry, not least to ensure that users do not have to repetitively give consent multiple times for each site they visit.

* To help publishers make it easier to gain consumers’ consent for their own purposes while maintaining a strong focus on privacy and trust.

C. Top free CMPs for publishers: 

1. Highest product adoption: Quantcast

* From the sites analyzed, Quantcast was live across the most sites.

* Quantcast was part of the IAB Steering Committee from early on, and as a result was instrumental in putting together the framework for the CMP.

* Features include language support, layout options and ability to revoke consent.

Market analysis: Best CMPs for publishers

For publishers wanting to dive deeper into the study, and look at the pros and cons of the best available CMPs in the market, here’s the report’s in-depth findings:

Top rated free CMPs

* All the exclusively free CMPs covered in this study scored relatively highly (between 60-70 out of a possible 100).

* The ‘lite’ versions of paid solutions performed the worst, with many features locked out of the free versions.

* There were some consistent features across all CMPs aimed at driving the highest possible conversion rates: the ability to configure consent buttons, not allowing the user to click out of the consent window (thus forcing consent).

Here is a list, with pros and cons, of the top 3 free CMPs from the study:

1. Quantcast

  1. Quantcast was part of the IAB Steering Committee from early on, and as a result was instrumental in putting together the framework for the CMP.
  2. They have a very high product adoption with the highest percentage of sites in the study using Quantcast’s CMP.
  3. Features include language support, layout options and ability to revoke consent.
  1. They do not offer sites the ability to view or analyze their consent metrics.
  2. Quantcast’s level of customer service has come in for criticism on occasions, a problem compounded by the complexity involved in implementing a CMP.

Score: 85/100

2. Captify

  1. One feature that the Captify CMP offers, which only a few other free CMPs are offering, is the ability to have a ‘disagree button’, giving consumers an easier way to control the use of their data.
  1. The Captify CMP is currently missing the ability to Control CMP messaging frequency around vendor list updates.

Score: 60/100

Top rated paid CMPs

Here is a list, with pros and cons, of the top 3 paid CMPs from the study:

1. iubenda

  1. Mandatory message, disagree button, and option for users to click off are all totally customizable features.
  2. Ability to choose from 600+ pre-crafted clauses in 8 languages, or add your own custom clauses using the built-in form, or place a request.
  3. Offline viewing available.
  1. It is unclear if they offer consent metrics and analytics.

Cost: The tailored version costs upwards from $2000 per year

2. Cookiebot

  1. One of the least expensive CMPs on the market, offering all of these features: Customize banner, customize declaration, multiple languages, email reports, data-export, geolocation, bulk consent, consent statistics, internal domain alias for development, test and staging.
  1. It is unclear if sites have the ability to customize the mandatory message.

Cost: £31 per month, per domain, and more than 5,000 subpages.

3. OneTrust

  1. Leverages your existing data map and inventory to meet GDPR Article 30 obligations.
  2. Multiple options for populating data flow inventory including questionnaires, scanning technology, in-person workshops, and bulk imports.
  3. Automatically generates searchable inventory and visual data maps based on your underlying data inventory.
  4. Includes PIA module to capture data flows from new projects.
  1. Payment options seem very confusing, with each additional item costing extra.


  • Assessment Automation: Fixed monthly subscriptions start at $500.
  • Data Inventory & Mapping: Fixed monthly subscriptions start at $500.
  • Cookie Compliance: Starts at $30/additional website.
  • Data Subject Access Request Portal: Fixed monthly subscriptions start at $150.                                                                                                                                                                                                                            .

Bubbling Under

4. Sourcepoint

  1. Supports authenticated consent across different regulatory regimes (GDPR/CCPA) and environments including Google AMP, iOS/Android, and most OTT devices
  2. Automatically flags privacy vulnerabilities which could lead to data leakages, non-compliance and brand safety issues.
  3. Allows for the creation of highly customized consent messages and user journeys.
  4. The platform is purpose-built for consent rate optimization.


  1. Better taken advantage of by an experienced ad ops manager or team. However, templates are available for a more out-of-the-box implementation.

Cost: Starts at 500 euros/month and is volume based.


What is the value in going for a paid for CMP over a free one?

Across all of the paid for CMPs, the features that were consistently available (and missing from the free versions) were:

  • Language options
  • More customization options such as layout, option for a disagree button and ability to alter the Terms and Conditions/ Privacy Policy
  • 24-hours support

Some of the more premium paid for CMPs also offer features such as:

  • The ability to scan from multiple geolocations
  • Custom reports and analytics
  • Multiple integration options, e.g.: via a widget, a link and hardcoded

The paid for CMPs range in price from $8 per month to $2000 per month depending on the features available and publisher size.

The majority of these charge on a per-site basis, meaning that networks would need to pay this fee for every site they want to implement the CMP on.

Closing thoughts

CMPs provide a clear way forward for publishers to manage their GDPR compliance obligations whilst enabling them to trade and communicate consent and data in a way that is compliant with GDPR.

While paid CMPs have certain additional benefits like language options and multiple integrations, the top free CMPs in the survey also offer great options. Of course, each CMP is different, and publishers will need to explore what works best for their requirements.

In this regard, the survey helps to narrow down the choices, from 100+ IAB registered CMPs available in the market, to the top 3 each in both free and paid categories, based on the features that publishers in both the UK and US are looking for.