diff --git a/.changeset/clean-chefs-impress.md b/.changeset/clean-chefs-impress.md
new file mode 100644
index 00000000..e41314fc
--- /dev/null
+++ b/.changeset/clean-chefs-impress.md
@@ -0,0 +1,5 @@
+---
+"@sigstore/oci": minor
+---
+
+Include `subject` and `artifactType` fields in artifact manifest for AWS ECR
diff --git a/packages/oci/src/image.ts b/packages/oci/src/image.ts
index 0019bbd3..5dc7148a 100644
--- a/packages/oci/src/image.ts
+++ b/packages/oci/src/image.ts
@@ -90,20 +90,15 @@ export class OCIImage {
 
       /* istanbul ignore if */
       if (this.#downgrade) {
-        delete manifest.subject;
-        delete manifest.artifactType;
-
         // ECR can't handle media types with parameters, so we need to strip the
         // version parameter from the Sigstore bundle media type.
+        manifest.artifactType = manifest.artifactType
+          ? manifest.artifactType.replace(/;.*/, '')
+          : undefined;
         manifest.layers[0].mediaType = manifest.layers[0].mediaType.replace(
           /;.*/,
           ''
         );
-
-        // ECR can't handle the "application/vnd.oci.empty.v1+json" media type
-        // for the config blob defined in OCI 1.1, so we need to use the Docker
-        // V2 API media type
-        manifest.config.mediaType = 'application/vnd.oci.image.config.v1+json';
       }
 
       // Upload artifact manifest