Didomi calculates and assigns a Trust Index for each vendor detected in our Compliance Report scanning process. This document describes how our Index is built.
What is the Trust Index?
The Trust Index is a value computed and assigned to each vendor based on a specific set of measurements used for estimating and evaluating vendor compliance.
Please note that our Compliance Report and Trust Index are meant as guides to be used in further consultations with your own DPO and legal team.
Measurements
We take a weighted average of the following:
- Declaration of Features & Purposes in the TCF IAB Global Vendor List (GVL) -> 60%
- The vendor’s country risk provided by the CNIL (French Data Protection Agency) -> 30%
- Didomi-assessed vigilance level of the vendor category -> 10%
1. IAB TCFv2 vendor declaration
If present in the GVL, the vendor must define its legal basis with:
- Purposes
- Flexible purposes
- Legitimate Interest purposes
- Legitimate Interest special purposes
- Features
- Special features
Each feature or purpose is assigned a value between 0 and 6.
| IAB purposes | Purpose Score | Flexible purpose score | Legitimate interest purpose score |
| 1. Store and/or access information on a device | 3 | 0 | N/A |
| 2. Select basic ads | 2 | 0 | 4 |
| 3. Create a personalised ads profile | 3 | 0 | 6 |
| 4. Select personalised ads | 3 | 0 | 6 |
|
5. Create a personalised content profile |
3 | 0 | 6 |
|
6. Select personalised content |
3 | 0 | 6 |
|
7. Measure ad performance |
1 | 0 | 2 |
|
8. Measure content performance |
1 | 0 | 2 |
| 9. Apply market research to generate audience insights | 2 | 0 | 4 |
| 10. Develop and improve products | 2 | 0 | 4 |
| IAB special purposes | |||
| 1. Ensure security prevent fraud and debug | 2 | ||
| 2. Technically deliver ads or content | 4 | ||
| IAB features | |||
| 1. Match and combine offline data sources | 5 | ||
| 2. Link different devices | 4 | ||
| 3. Receive and use automatically sent device characteristics for identification | 4 | ||
| IAB special features | |||
| 1. Use precise geolocation data | 5 | ||
| 2. Actively scan device characteristics for identification | 4 |
We then proceed to calculate an average score as follows:
Step 1: We add up all the values for each purpose and feature
Step 2: We verify the total value and assign a score as follows:
| Total value | Average Score |
| > 45 | 5 |
| between 35 and 45 | 4 |
| between 25 and 35 | 3 |
| between 15 and 25 | 2 |
| between 0 and 15 | 1 |
All vendors not declared in the IAB will automatically be assigned an Average Score of 4
2. Vendor country risk
We assign a "country vigilance level" (score) based on the CNIL country dataset:
| Country adequacy | Score |
| EU or EES member country | 1 |
| GDPR-adequate country | 1 |
| Partially GDPR-adequate country | 3 |
| Independent authority and law(s) | 4 |
| With legislation | 4 |
| No laws | 5 |
| N/A | 5 |
3. Vendor category vigilance level
A vendor "category vigilance level" (score) is defined by Didomi, based on analysis carried out with the SRI (French advertising management union) and the GESTE (Professional publishers network).
| Vendor Category | Score |
| NIA > NIA | 2 |
| Advertising & Affiliation > Advertising | 3 |
| Advertising & Affiliation > Affiliation | 4 |
| CRM & Martech > Marketing Automation | 5 |
| CRM & Martech >Voice of Consumer | 5 |
| Social media and advertising > Social media and advertising | 5 |
| Tracking & Analytics > Audience Analytics | 4 |
| Tracking & Analytics > Customer Data Platform | 4 |
| Tracking & Analytics > Performance Attribution | 4 |
| Tracking & Analytics > View-ability, Fraud | 2 |
| Tracking & Analytics > Customer Identity Management | 5 |
| Tracking & Analytics > Data Enhancement | 5 |
| Essentials > Web performance | 1 |
| Essentials > Tag Management System | 2 |
| Essentials > Privacy CMP | 1 |
| Essentials > Content Deliver Network | 2 |
| Essentials > Javascript libraries | 3 |
| Essentials > Security Malware | 1 |
| Essentials > Authentication | 3 |
| Essentials > Player | 3 |
| Essentials > Fonts | 1 |
|
Widget > Widget |
3 |
| Publisher > News & Media | 2 |
| Publisher > Retail & Services | 2 |
| Publisher > Audio Video Platform | 2 |
| Publisher > Gov | 1 |
Final calculation
Total scores for each section are multiplied by the following weighting:
- 60% for IAB TCFv2 vendor declaration
- 30% for vendor country risk
- 10% for Didomi vendor category vigilance level
The result is a value between 0 and 1, mapped accordingly:
| Value | Final Score |
| between 0 and 0.2 | Very high |
| between 0.2 and 0.4 | High |
| between 0.4 and 0.6 | Medium |
| between 0.6 and 0.8 | Low |
| between 0.8 and 1 | Very low |