bucketKeyEnabled

Specifies whether Amazon S3 should use an S3 Bucket Key for object encryption with server-side encryption using Key Management Service (KMS) keys (SSE-KMS). If a target object uses SSE-KMS, you can enable an S3 Bucket Key for the object.

Setting this header to true causes Amazon S3 to use an S3 Bucket Key for object encryption with SSE-KMS. Specifying this header with a COPY action doesn’t affect bucket-level settings for S3 Bucket Key.

For more information, see Amazon S3 Bucket Keys in the Amazon S3 User Guide.

Directory buckets - S3 Bucket Keys aren't supported, when you copy SSE-KMS encrypted objects from general purpose buckets to directory buckets, from directory buckets to general purpose buckets, or between directory buckets, through CopyObject. In this case, Amazon S3 makes a call to KMS every time a copy request is made for a KMS-encrypted object.