Data Publishing @ Mozilla


Mozilla’s history is steeped in openness and transparency –  it’s simply core to what we do and how we see ourselves in the world.  We are always looking  for ways to bring our mission to life in ways that help create a healthy internet and support the Mozilla Manifesto.  One of  our commitments says  “We are committed to an internet that elevates critical thinking, reasoned argument, shared knowledge, and verifiable facts”.

To this end, we have spent a good amount of time considering how we can publicly share  our Mozilla telemetry data sets – it is one of the most simple and effective ways we can enable collaboration and share knowledge.  But, only if it can be done safely and in a privacy protecting, principled way. We believe we’ve designed a way to do this and we are excited to outline our approach here.

Making data public not only  allows us to be transparent about our data practices, but directly demonstrates how our work contributes to our mission. Having a publicly available methodology for vetting and sharing our data demonstrates our values as a company. It will also enable other research opportunities with trusted scientists, analysts, journalists, and policymakers in a way that furthers our efforts to shape an internet that benefits everyone.

Dataset Publishing Process

We want our data publishing review process, as well as our review decisions to be public and understandable, similar to our Mozilla  Data Collection program. To that end, our full dataset publishing policy and details about what considerations we look at before determining what is safe to publish can be found on our wiki here.  Below is a summary of the critical pieces of that process.

The goal of our data publishing process is to:

  • Reduce friction for data publishing requests with low privacy risk to users;
  • Have a review system of checks and balances that considers both data aggregations and data level sensitivities to determine privacy risk prior to publishing, and;
  • Create a public record of these reviews,  including making data and the queries that generate it publicly available and putting a link to the dataset + metadata on a public-facing Mozilla property.

Having a dataset published requires filling out a publicly available request on Bugzilla.  Requesters will answer a series of questions, including information about aggregation levels, data collection  categories, and dimensions or metrics that include sensitive data.

A data steward will review the bug request.  They will help ensure the questions are correctly answered and determine if the data can be published or whether it requires review by our Trust & Security or  Legal teams.

When a request is approved, our telemetry data engineering team will:

  • Write (or review) the query
  • Schedule it to update on the desired frequency
  • Include it in the pubic facing dataset infrastructure, including metadata that links the public data back to the  review bug.

Finally, once the dataset is published, we’ll announce it on the Data @ Mozilla blog. It will also be added to

Want to know more?

Questions? Contact us at