diff --git a/fep/c390/fep-c390.feature b/fep/c390/fep-c390.feature
new file mode 100644
index 0000000..0c82e61
--- /dev/null
+++ b/fep/c390/fep-c390.feature
@@ -0,0 +1,72 @@
+Feature: FEP-c390: Identity Proofs
+
+    @fep-c390
+    Scenario: Creating the identity proof
+        Given the decentralized identifier "did:key:z6MkrJVnaZkeFzdQyMZu1cgjg7k1pZZ6pvBQ7XJPt4swbTQ2"
+        And private Key "z3u2en7t5LR2WtQH5PfFqMqwVHBeXouLzo6haApm8XHqvjxq"
+        And actor ID "https://server.example/users/alice"
+        And current time "2023-02-24T23:36:38Z"
+        When creating the identity proof for the actor
+        Then the identity claim is
+            """
+             {
+                "type": "VerifiableIdentityStatement",
+                "subject": "did:key:z6MkrJVnaZkeFzdQyMZu1cgjg7k1pZZ6pvBQ7XJPt4swbTQ2",
+                "alsoKnownAs": "https://server.example/users/alice"
+            }
+            """
+        And the identity proof is
+            """
+            {
+                "type": "VerifiableIdentityStatement",
+                "subject": "did:key:z6MkrJVnaZkeFzdQyMZu1cgjg7k1pZZ6pvBQ7XJPt4swbTQ2",
+                "alsoKnownAs": "https://server.example/users/alice",
+                "proof": {
+                    "type": "DataIntegrityProof",
+                    "cryptosuite": "jcs-eddsa-2022",
+                    "created": "2023-02-24T23:36:38Z",
+                    "verificationMethod": "did:key:z6MkrJVnaZkeFzdQyMZu1cgjg7k1pZZ6pvBQ7XJPt4swbTQ2",
+                    "proofPurpose": "assertionMethod",
+                    "proofValue": "zYqr4eFzrnUWiBDaa7SmBhfaSBiv6BFRsDRGkmaCJpXArPBspFWNM6NXu77R7JakdzbUdjZihBa28LuWscZxSfRk"
+                }
+            }
+            """
+
+    @fep-c390
+    Scenario: Verifying the identity proof
+        Given the actor
+            """
+            {
+                "@context": [
+                    "https://www.w3.org/ns/activitystreams",
+                    "https://www.w3.org/ns/did/v1",
+                    "https://w3id.org/security/data-integrity/v1",
+                    {
+                        "fep": "https://w3id.org/fep#",
+                        "VerifiableIdentityStatement": "fep:VerifiableIdentityStatement",
+                        "subject": "fep:subject"
+                    }
+                ],
+                "type": "Person",
+                "id": "https://server.example/users/alice",
+                "inbox": "https://server.example/users/alice/inbox",
+                "outbox": "https://server.example/users/alice/outbox",
+                "attachment": [
+                    {
+                        "type": "VerifiableIdentityStatement",
+                        "subject": "did:key:z6MkrJVnaZkeFzdQyMZu1cgjg7k1pZZ6pvBQ7XJPt4swbTQ2",
+                        "alsoKnownAs": "https://server.example/users/alice",
+                        "proof": {
+                            "type": "DataIntegrityProof",
+                            "cryptosuite": "jcs-eddsa-2022",
+                            "created": "2023-02-24T23:36:38Z",
+                            "verificationMethod": "did:key:z6MkrJVnaZkeFzdQyMZu1cgjg7k1pZZ6pvBQ7XJPt4swbTQ2",
+                            "proofPurpose": "assertionMethod",
+                            "proofValue": "zYqr4eFzrnUWiBDaa7SmBhfaSBiv6BFRsDRGkmaCJpXArPBspFWNM6NXu77R7JakdzbUdjZihBa28LuWscZxSfRk"
+                        }
+                    }
+                ]
+            }
+            """
+        When verifying the attached identity proof
+        Then the identity proof is valid
diff --git a/fep/c390/fep-c390.md b/fep/c390/fep-c390.md
index c54c348..55c6338 100644
--- a/fep/c390/fep-c390.md
+++ b/fep/c390/fep-c390.md
@@ -36,7 +36,7 @@ Identity proofs SHOULD be attached to an actor object, under the `attachment` pr
 
 ### Proof generation
 
-The identity proof document MUST contain a data integrity proof, which includes a cryptographic proof and parameters required to verify it. It MUST be created according to the *Data Integrity* specification, section [4.1 Generate Proof](https://w3c.github.io/vc-data-integrity/#generate-proof). The value of `verificationMethod` property of the data integrity proof MUST match the value of `subject` property of the identity proof document.
+The identity proof document MUST contain a data integrity proof, which includes a cryptographic proof and parameters required to verify it. It MUST be created according to the *Data Integrity* specification, section [4.1 Add Proof](https://w3c.github.io/vc-data-integrity/#add-proof). The value of `verificationMethod` property of the data integrity proof MUST match the value of `subject` property of the identity proof document.
 
 The resulting data integrity proof MUST be added to identity proof document under the `proof` key.
 
@@ -61,15 +61,15 @@ Example:
     "attachment": [
         {
             "type": "VerifiableIdentityStatement",
-            "subject": "did:key:z6MkhaXgBZDvotDkL5257faiztiGiC2QtKLGpbnnEGta2doK",
+            "subject": "did:key:z6MkrJVnaZkeFzdQyMZu1cgjg7k1pZZ6pvBQ7XJPt4swbTQ2",
             "alsoKnownAs": "https://server.example/users/alice",
             "proof": {
                 "type": "DataIntegrityProof",
                 "cryptosuite": "jcs-eddsa-2022",
-                "created": "2022-11-12T00:00:00Z",
-                "verificationMethod": "did:key:z6MkhaXgBZDvotDkL5257faiztiGiC2QtKLGpbnnEGta2doK",
+                "created": "2023-02-24T23:36:38Z",
+                "verificationMethod": "did:key:z6MkrJVnaZkeFzdQyMZu1cgjg7k1pZZ6pvBQ7XJPt4swbTQ2",
                 "proofPurpose": "assertionMethod",
-                "proofValue": "<proof-value>"
+                "proofValue": "zYqr4eFzrnUWiBDaa7SmBhfaSBiv6BFRsDRGkmaCJpXArPBspFWNM6NXu77R7JakdzbUdjZihBa28LuWscZxSfRk"
             }
         }
     ]
@@ -88,6 +88,14 @@ The consuming implementations SHOULD treat identities denoted by `subject` and `
 
 If two actors have identity proofs with the same `subject` property, they SHOULD be treated as different identities of the same entity.
 
+## Test vectors
+
+See [fep-c390.feature](./fep-c390.feature)
+
+## Implementations
+
+- [Mitra](https://codeberg.org/silverpill/mitra/src/commit/eb18e475efb71e461cd33c800c86cfe94144f5a3/FEDERATION.md#identity-proofs)
+
 ## References
 
 - [ActivityPub] Christine Lemmer Webber, Jessica Tallon, [ActivityPub](https://www.w3.org/TR/activitypub/), 2018