Amazon API Gateway now supports mutual TLS with certificates from third-party CAs and ACM Private CA

Amazon API Gateway enables customers to authenticate clients using certificate-based mutual TLS, where digital certificates are exchanged between the client and API Gateway before a secure connection is established. Previously, only certificates issued by AWS Certificate Manager (ACM) could be used as the server certificate when configuring mutual TLS in API Gateway. Starting today, customers can use a server certificate issued by a third-party certificate authority (CA) or ACM Private CA.

Source:: Amazon AWS