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Businesses that serve customers in the European Union (EU) and European Economic Area (EEA) must comply with strict data privacy laws, such as the General Data Protection Regulation (GDPR). These regulations require companies to obtain explicit user consent before collecting, storing, or sharing personal data, especially for marketing and analytics purposes. Google has responded to this need by developing two key consent management tools: Google Consent Mode (GCM) and Google Additional Consent Mode (GACM).

While they may sound similar, Google Consent Mode and Google Additional Consent Mode serve different purposes and work in distinct ways. Understanding their differences and how to implement both correctly is crucial for businesses that rely on Google services for analytics, advertising, and data-driven marketing strategies.

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What Is Google Consent Mode?

Google Consent Mode (GCM) is a technical framework designed to help businesses comply with EU and EEA data privacy regulations without compromising data collection for analytics and advertising purposes. Released as part of Google’s effort to align with privacy laws, GCM allows website owners to adjust the behavior of Google services based on user consent preferences. It essentially acts as a bridge between user consent choices and the data processing carried out by tools like Google Analytics 4 and Google Ads.

With GCM, when users visit a website, their consent preferences—whether they agree to or decline data collection—are communicated to Google via consent signals embedded in the website’s code. If a user agrees, the full range of data can be collected and processed. However, if they decline, GCM limits or modifies the data that is collected to respect the user’s preferences.

Key Features of Google Consent Mode:

  1. Real-Time Consent Communication: GCM uses consent signals to communicate user preferences to Google services in real-time. These signals adjust how Google Analytics, Google Ads, and other services collect data.
  2. Data Modeling to Fill Gaps: In cases where users decline consent, GCM uses advanced data modeling to estimate the missing data. This feature ensures businesses continue to receive meaningful insights even when full tracking is not allowed.
  3. Compatibility with Privacy Regulations: GCM aligns with major data privacy laws such as the GDPR, ensuring compliance with the EU’s stringent consent requirements.
  4. Required for Google Services in the EU/EEA: From March 2024, websites that use Google Analytics 4 or Google Ads must implement GCM v2 if they target users in the EU/EEA.
    • How It Works: Google Consent Mode works by controlling the behavior of cookies and tags through four key consent signals:
        • ad_storage: Controls whether ads can be personalized based on user data.
        • analytics_storage: Controls whether analytics cookies can be used to track user behavior.
        • ad_user_data: Manages the sharing of user data specifically for targeted advertising.
        • ad_personalization: Manages whether ads are tailored based on user preferences and behavior.

When a user interacts with the consent banner on a website, their preferences are recorded and communicated to Google through these signals. If a user declines consent, GCM ensures that tracking cookies do not collect data related to their behavior, while leveraging data modeling techniques to approximate what might have been collected.

What Is Google Additional Consent Mode?

Google Additional Consent Mode (GACM) is another technical specification that works alongside the Transparency and Consent Framework (TCF) v2.2 from IAB Europe. It provides a way for websites to gather consent for ad technology providers (ATPs) that are not registered with IAB Europe’s Global Vendor List (GVL) but are part of Google’s Ad Tech Providers (ATP) list.

In essence, GACM allows website owners to expand the list of third-party vendors that can receive consent signals beyond those recognized by the IAB framework. This feature is crucial for businesses that want to use a broader range of ad networks and service providers while still complying with GDPR and TCF v2.2.

Key Features of Google Additional Consent Mode:

  1. Compatibility with TCF v2.2: GACM is specifically designed to complement the Transparency and Consent Framework (TCF), which many websites use to manage user consent.
  2. Support for Non-IAB Vendors: Unlike GCM, GACM allows websites to communicate consent preferences to vendors outside of the IAB Global Vendor List. These include Google Ad Tech Providers (ATP) who are not registered with IAB but can still serve ads to users.
  3. Extended Consent Scope: Websites can gather and share user consent with a wider range of ad vendors, giving them more flexibility in their advertising strategies.
    • How It Works: GACM operates by using an Additional Consent string, which is a line of code added to a website’s consent management framework. This string records which ad technology providers (ATPs) outside the IAB GVL have received user consent. The Additional Consent string works alongside the TC string, which is the core component of TCF v2.2. Together, these strings allow websites to manage consent for a broader group of vendors, thus increasing ad inventory while staying compliant with privacy regulations.

Key Differences

Although both GCM and GACM are used to manage user consent, there are notable differences between the two systems in terms of functionality, scope, and the type of vendors they affect.

Google Consent Mode (GCM) Google Additional Consent Mode (GACM)
Primary Function

Manages user consent for Google services like Ads and Analytics.

Manages consent for Google Ad Tech Providers (ATPs) outside of IAB’s GVL.
Required for Websites using Google Ads, Google Analytics 4, and Floodlight tags. Websites using Google Ad Manager, AdSense, and AdMob.
Scope of Vendors Limited to vendors within the Google ecosystem. Extends to non-IAB ATPs via the Additional Consent string.
Data Modeling Includes advanced data modeling to fill in gaps when consent is declined. No data modeling feature.
Regulation Compliance Required for compliance with GDPR and DMA. Works with IAB Europe’s voluntary TCF v2.2 framework.

Similarities 

Despite their differences, both GCM and GACM share some common characteristics:

  1. Compliance with GDPR: Both tools are designed to help businesses comply with EU data privacy laws, ensuring that user data is collected and processed only with consent.
  2. Google Tag Integration: Both GCM and GACM use Google Tags rather than cookies to send consent signals. This ensures that consent preferences are communicated accurately across third-party services.
  3. CMP Integration: Both consent modes can be implemented using a Google-certified Consent Management Platform (CMP). This software helps websites collect, manage, and transmit user consent data effectively.
  4. Support for First-Party and Third-Party Tracking: Both GCM and GACM support tracking efforts for both the publisher (first-party) and third-party advertisers (e.g., Google Ads, ATPs).

Who Must Use Google Consent Mode?

  • Any business that uses Google Ads, Google Analytics 4, or other Google services to monitor and serve ads to users in the EU/EEA must implement Google Consent Mode by March 2024. This requirement applies to companies that want to continue receiving data from Google’s analytics and advertising tools. Without GCM, these businesses may lose access to valuable marketing insights and risk non-compliance with EU data privacy laws, which could result in fines or penalties.

Who Must Use Google Additional Consent Mode?

  • Businesses that use Google AdSense, AdMob, or Ad Manager to serve ads in the EU/EEA or the UK should implement Google Additional Consent Mode if they rely on ad vendors not included in the IAB’s Global Vendor List. Implementing GACM ensures that consent is managed properly for all ad technology providers, allowing these businesses to expand their ad inventory while maintaining GDPR compliance. The deadline for switching to a CMP that supports Additional Consent was January 16, 2024.

The Importance of a Consent Management Platform (CMP)

Both Google Consent Mode and Google Additional Consent Mode rely on a Consent Management Platform (CMP) to function correctly. A CMP is essential for managing the consent process and ensuring that user data is handled in accordance with privacy regulations. It helps websites:

  1. Display consent banners that allow users to opt in or out of data collection.
  2. Record user consent preferences and communicate these to relevant vendors.
  3. Ensure compliance with GDPR, TCF v2.2, and other privacy frameworks.

Many CMPs are designed to work seamlessly with both GCM and GACM, allowing businesses to manage consent for a wide range of vendors and data processing activities.

Wrapping Up

Where data privacy is increasingly scrutinized, tools like Google Consent Mode and Google Additional Consent Mode offer businesses a way to balance compliance with effective data collection. While they serve different purposes, both tools are essential for companies operating in the EU/EEA that rely on data-driven marketing strategies.

Understanding the differences and similarities between GCM and GACM is key to implementing the right solution for your business. Whether you’re managing user consent for Google Ads, Google Analytics, or third-party ad technology providers, these tools provide the flexibility and compliance needed to protect user privacy without compromising the effectiveness of your marketing efforts.

For additional support, resources, & more, consider utilizing GetTerms. For more information, you can visit our website here. We offer a simple solution, ensuring you meet legal standards while maintaining user confidence in your data handling practices. Create an account and get started in 5 minutes. For any further questions or assistance, the GetTerms support team is always ready to help.

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