Data security is a massive priority here at Merge, and we know it is for our customers too! This is why we added the ability to sync only the data you need and avoid storing any data you do not want passed through Merge.
If you are a signed customer on our Grow and Expand plans, you can check out the Common Models tab in the Configuration section of your Merge app, where you can set what data you want to sync via Merge at the common model or field level!
Disabling a field or common model means that Merge will no longer store that data to our database. However, data that already exists for the disabled fields or models will not be deleted and will still be available via Merge endpoints.