diff --git a/src/main/java/uk/ac/ox/ctl/ltiauth/JWTService.java b/src/main/java/uk/ac/ox/ctl/ltiauth/JWTService.java
index d6acd20..dcca6f0 100644
--- a/src/main/java/uk/ac/ox/ctl/ltiauth/JWTService.java
+++ b/src/main/java/uk/ac/ox/ctl/ltiauth/JWTService.java
@@ -33,7 +33,6 @@ public JWTService(JWTSigner signer, JWTStore store, LtiSettings ltiSettings) {
      */
     public String createJWT(OAuth2AuthenticationToken token, String toolSupportUrl) {
         JWTClaimsSet.Builder builder = new JWTClaimsSet.Builder();
-        checkForNullCustomValues(token);
         token.getPrincipal().getAttributes().forEach(builder::claim);
         builder
                 // Save the original issuer, this is needed for deep linking where we need to know who the audience is.
@@ -49,21 +48,6 @@ public String createJWT(OAuth2AuthenticationToken token, String toolSupportUrl)
             throw new BadCredentialsException("Failed to create new JWT");
         }
     }
-    
-    void checkForNullCustomValues(OAuth2AuthenticationToken token) {
-        // Checks if any of the launches we handle currently get a null value
-        // This is only needed for a short time while we are checking if there's anything we should be looking
-        // at. Once Canvas has released the change to production we can remove this as we will be seeing the 
-        // errors.
-        Object claim = token.getPrincipal().getAttribute("https://purl.imsglobal.org/spec/lti/claim/custom");
-        if (claim instanceof Map custom) {
-            custom.forEach((key, value) -> {
-                if (value == null) {
-                    log.error("Custom attribute {} is null for client registration ID: {}", key, token.getAuthorizedClientRegistrationId());
-                }
-            });
-        }
-    }
 
     public String store(Object token) {
         return store.store(token);
diff --git a/src/test/java/uk/ac/ox/ctl/ltiauth/JWTServiceTest.java b/src/test/java/uk/ac/ox/ctl/ltiauth/JWTServiceTest.java
deleted file mode 100644
index 6d1952a..0000000
--- a/src/test/java/uk/ac/ox/ctl/ltiauth/JWTServiceTest.java
+++ /dev/null
@@ -1,50 +0,0 @@
-package uk.ac.ox.ctl.ltiauth;
-
-import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.Nested;
-import org.junit.jupiter.api.Test;
-import org.springframework.security.oauth2.client.authentication.OAuth2AuthenticationToken;
-import org.springframework.security.oauth2.core.user.OAuth2User;
-
-import static java.util.Collections.singletonMap;
-import static org.mockito.Mockito.mock;
-import static org.mockito.Mockito.when;
-
-class JWTServiceTest {
-
-    @Nested
-    public class CheckingClaims {
-        // These tests are to make sure we aren't going to blow up with bad token values.
-        // Checking the logger does the right thing isn't worth the complexity
-        
-        private JWTService service;
-        private OAuth2User user;
-
-        @BeforeEach
-        public void setUp() {
-            service = new JWTService(mock(JWTSigner.class), mock(JWTStore.class), mock(LtiSettings.class));
-            user = mock(OAuth2User.class);
-        }
-        
-        @Test
-        public void noMap() {
-            OAuth2AuthenticationToken token = new OAuth2AuthenticationToken(user, null, "test");
-            service.checkForNullCustomValues(token);
-        }
-
-        @Test
-        public void goodClaim() {
-            when(user.getAttribute("https://purl.imsglobal.org/spec/lti/claim/custom")).thenReturn(singletonMap("key", "value"));
-            OAuth2AuthenticationToken token = new OAuth2AuthenticationToken(user, null, "test");
-            service.checkForNullCustomValues(token);
-        }
-
-        @Test
-        public void nullClaim() {
-            when(user.getAttribute("https://purl.imsglobal.org/spec/lti/claim/custom")).thenReturn(singletonMap("key", null));
-            OAuth2AuthenticationToken token = new OAuth2AuthenticationToken(user, null, "test");
-            service.checkForNullCustomValues(token);
-        }
-    }
-
-}
\ No newline at end of file