diff --git a/suites/verify.js b/suites/verify.js
index dd2a340..8570b15 100644
--- a/suites/verify.js
+++ b/suites/verify.js
@@ -165,8 +165,20 @@ export function runDataIntegrityProofVerifyTests({
       'at the end of the value, or with a time zone offset relative ' +
       'to UTC.', async function() {
         this.test.link = 'https://w3c.github.io/vc-data-integrity/#proofs:~:text=MUST%20be%20specified%20as%20an%20%5BXMLSCHEMA11%2D2%5D%20dateTimeStamp%20string%2C%20either%20in%20Universal%20Coordinated%20Time%20(UTC)%2C%20denoted%20by%20a%20Z%20at%20the%20end%20of%20the%20value%2C%20or%20with%20a%20time%20zone%20offset%20relative%20to%20UTC';
-        const credential = credentials.clone('invalidCreated');
-        await verificationFail({credential, verifier});
+        await verificationFail({
+          credential: credentials.clone('invalidCreated'),
+          verifier
+        });
+      });
+      it('If present (expires), it MUST be an [XMLSCHEMA11-2] dateTimeStamp ' +
+      'string, either in Universal Coordinated Time (UTC), denoted by a Z ' +
+      'at the end of the value, or with a time zone offset relative to UTC.',
+      async function() {
+        this.test.link = 'https://w3c.github.io/vc-data-integrity/#proofs:~:text=If%20present%2C%20it%20MUST%20be%20an%20%5BXMLSCHEMA11%2D2%5D%20dateTimeStamp%20string%2C%20either%20in%20Universal%20Coordinated%20Time%20(UTC)%2C%20denoted%20by%20a%20Z%20at%20the%20end%20of%20the%20value%2C%20or%20with%20a%20time%20zone%20offset%20relative%20to%20UTC.';
+        await verificationFail({
+          credential: credentials.clone('invalidExpires'),
+          verifier
+        });
       });
       // we can't tell if its interpreted correctly but we can ensure their
       // verifier at least takes timestamps without Z or an offset.
diff --git a/vc-generator/generators.js b/vc-generator/generators.js
index bf9004f..4346c10 100644
--- a/vc-generator/generators.js
+++ b/vc-generator/generators.js
@@ -17,6 +17,7 @@ export const generators = {
     noOffsetCreated,
     noOffsetExpires,
     invalidCreated,
+    invalidExpires,
     createdOneYearAgo
   },
   // creates test vectors for Authentication Purpose tests
@@ -173,13 +174,23 @@ function noVerificationMethod({suite, selectiveSuite, credential, ...args}) {
   return {...args, suite, selectiveSuite, credential};
 }
 
-function invalidCreated({suite, selectiveSuite, credential, ...args}) {
+function invalidCreated({suite, selectiveSuite, ...args}) {
   // suite.date will be used as created when signing
   suite.date = 'invalidDate';
   if(selectiveSuite) {
     selectiveSuite.date = 'invalidDate';
   }
-  return {...args, suite, selectiveSuite, credential};
+  return {...args, suite, selectiveSuite};
+}
+
+function invalidExpires({suite, selectiveSuite, ...args}) {
+  suite.proof = suite.proof || {};
+  suite.proof.expires = 'invalidDate';
+  if(selectiveSuite) {
+    selectiveSuite.proof = selectiveSuite.proof || {};
+    selectiveSuite.proof.expires = 'invalidDate';
+  }
+  return {...args, suite, selectiveSuite};
 }
 
 function createdOneYearAgo({
@@ -214,7 +225,8 @@ function invalidProofType({
   suite.type = proofType;
   if(selectiveSuite) {
     const proofId = 'urn:uuid:no-proof-type-test';
-    suite.proof = {id: proofId};
+    suite.proof = suite.proof || {};
+    suite.proof.id = proofId;
     selectiveSuite._cryptosuite.options.proofId = proofId;
     selectiveSuite.type = proofType;
   }
@@ -252,11 +264,13 @@ function noOffsetCreated({suite, selectiveSuite, ...args}) {
 }
 
 function noOffsetExpires({suite, selectiveSuite, ...args}) {
-  const expires = new Date().toISOString().replace(/\.\d+Z$/, '');
   // lop off ms precision from ISO timestamp
-  suite.proof = {expires};
+  const expires = new Date().toISOString().replace(/\.\d+Z$/, '');
+  suite.proof = suite.proof || {};
+  suite.proof.expires = expires;
   if(selectiveSuite) {
-    selectiveSuite.proof = {...suite.proof, ...selectiveSuite.proof};
+    selectiveSuite.proof = selectiveSuite.proof || {};
+    selectiveSuite.proof.expires = expires;
   }
   return {...args, suite, selectiveSuite};
 }