Parameter Store, a capability of AWS Systems Manager that provides secure storage for configuration data, now allows you to share advanced-tier parameters with other AWS accounts, enabling you to centrally manage your configuration data. Parameters are key-value pairs that you can reference in code and through several AWS integrations such as AWS CloudFormation and Amazon EC2. Today, many customers have workloads in multiple AWS accounts that depend on shared configuration data. Now, you can maintain a single source of truth for configuration data by sharing parameters with other accounts that need access rather than manually duplicating and synchronizing data across accounts.
Source:: Amazon AWS