Self-hosted data with IAM delegated access is a mechanism that allows users to host their own data in an S3 bucket while still being able to use Scale's annotation platform.

Instead of using a VPN and adding specific IP addresses, this method utilizes IAM delegated access, which allows Scale to sign the images hosted in the user's S3 bucket on their behalf and display them to annotators without storing the images on Scale's side.

This allows for more flexibility in managing access to the data, as users can create a wildcard IP address for users in their VPN instead of updating the policy for each individual.

The process involves setting up S3 IAM access, creating a new project for this, and using s3:// URLs instead of https:// URLs when creating tasks via API.