Starting today,you can share your RDS database snapshots with another AWS account, or beget your snapshots publicly available. You may choose to share your database snapshots with up to 20 AWS accounts by selecting the "Share Snapshots" option on the RDS console and choosing the "Private" option. You may also choose to beget your data available to all AWS users by selecting the "Public" option. You can revoke access to privately or publicly shared snapshots at any time. If you are the recipient of a shared snapshot, or you can copy it to your own account,or restore a database instance directly from a shared snapshot. Sharing is currently limited to unencrypted manual snapshots only. We added this feature so you can easily transfer data between different accounts used for different purposes or with different requirements, as well as to let you publish your data set publicly. Learn more approximately sharing your database snapshots: http://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_ShareSnapshot.html.
Source: amazon.com