Launching isolated ARA experiment for Privacy Sandbox origin trial

[Kevin Lee]

To improve our testing process, we are creating isolated experiments for each of the origin trial APIs, in addition to the existing unified experiment. The new Attribution Reporting API isolated experiment will receive 1% of new Stable traffic on top of the existing 5% of Stable traffic from the unified experiment.

The isolated experiment will launch on Monday, March 13, 2023, and you will begin to receive a total of 6% of the Stable traffic for Attribution Reporting (5% from the unified experiment and 1% from the new isolated experiment).

For a deeper dive into these changes, please see the Relevance and measurement unified origin trial article on the Chrome blog. If you have any questions on this change, please file an issue in the Attribution Reporting API GitHub repository.