diff --git a/README.adoc b/README.adoc
index 100dc23..a44babb 100644
--- a/README.adoc
+++ b/README.adoc
@@ -3,7 +3,7 @@
 == HiveMQ Deny Wildcard Subscription Extension
 *Extension Type*: Security
 
-*Version*: 4.0.0
+*Version*: 4.1.1
 
 *License*: Apache License 2.0
 
@@ -21,7 +21,8 @@ This extension denies any subscription to the root wildcard topic. In general, r
 No configuration needed, works out of the box.
 
 === First Steps
-After the extension is installed start HiveMQ. Now no client is allowed to subscribe to `#`.
+After the extension is installed start HiveMQ. Now no client is allowed to subscribe to `#`, `+/#`, `$share/group/#`
+or any other topic filter that would represent a root wildcard.
 
 ==== Need help?
 
diff --git a/pom.xml b/pom.xml
index 4ee3976..6f75ec3 100644
--- a/pom.xml
+++ b/pom.xml
@@ -20,7 +20,7 @@
 
     <groupId>com.hivemq.extension</groupId>
     <artifactId>hivemq-deny-wildcard-extension</artifactId>
-    <version>4.1.0</version>
+    <version>4.1.1</version>
     <description>HiveMQ Extension to deny top level wildcard subscription</description>
     <inceptionYear>2018</inceptionYear>
 
diff --git a/src/main/java/com/hivemq/extension/callbacks/DenyWildcardAuthorizer.java b/src/main/java/com/hivemq/extension/callbacks/DenyWildcardAuthorizer.java
index e4fc0ee..0b751c9 100644
--- a/src/main/java/com/hivemq/extension/callbacks/DenyWildcardAuthorizer.java
+++ b/src/main/java/com/hivemq/extension/callbacks/DenyWildcardAuthorizer.java
@@ -25,6 +25,7 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
 
@@ -41,7 +42,8 @@
 public class DenyWildcardAuthorizer implements SubscriptionAuthorizer {
 
     public static final DenyWildcardAuthorizer INSTANCE = new DenyWildcardAuthorizer();
-    public static final String REASON_STRING = "Root wildcard subscription not supported.";
+    public static final String REASON_STRING = "Root wildcard subscriptions are not supported.";
+    private static final Pattern SHARED_SUBSCRIPTION_PATTERN = Pattern.compile("\\$share(/.*?/(.*))");
 
     private DenyWildcardAuthorizer() {
     }
@@ -52,6 +54,18 @@ private DenyWildcardAuthorizer() {
     @Override
     public void authorizeSubscribe(@NotNull final SubscriptionAuthorizerInput subscriptionAuthorizerInput, @NotNull final SubscriptionAuthorizerOutput subscriptionAuthorizerOutput) {
         final String topicFilter = subscriptionAuthorizerInput.getSubscription().getTopicFilter();
+
+        if (topicFilter.startsWith("$share/")) {
+            final Matcher matcher = SHARED_SUBSCRIPTION_PATTERN.matcher(topicFilter);
+            if (matcher.matches()) {
+                final String subscriptionTopic = matcher.group(2);
+                if (StringUtils.containsOnly(subscriptionTopic, WILDCARD_CHARS)) {
+                    logger.debug("Client {} tried to subscribe to an denied shared root wildcard topic filter '{}'", subscriptionAuthorizerInput.getClientInformation().getClientId(), topicFilter);
+                    subscriptionAuthorizerOutput.failAuthorization(SubackReasonCode.NOT_AUTHORIZED, REASON_STRING);
+                }
+            }
+        }
+
         if (StringUtils.containsOnly(topicFilter, WILDCARD_CHARS)) {
             logger.debug("Client {} tried to subscribe to an denied root wildcard topic filter '{}'", subscriptionAuthorizerInput.getClientInformation().getClientId(), topicFilter);
             subscriptionAuthorizerOutput.failAuthorization(SubackReasonCode.NOT_AUTHORIZED, REASON_STRING);
diff --git a/src/test/java/com/hivemq/extension/callbacks/DenyWildcardAuthorizerTest.java b/src/test/java/com/hivemq/extension/callbacks/DenyWildcardAuthorizerTest.java
index 486c1d7..29fcb76 100644
--- a/src/test/java/com/hivemq/extension/callbacks/DenyWildcardAuthorizerTest.java
+++ b/src/test/java/com/hivemq/extension/callbacks/DenyWildcardAuthorizerTest.java
@@ -63,61 +63,62 @@ public void test_denied_hashtag() {
     }
 
     @Test
-    public void test_denied_plus() {
-        when(input.getSubscription().getTopicFilter()).thenReturn("+");
+    public void test_denied_shared_hash() {
+        when(input.getSubscription().getTopicFilter()).thenReturn("$share/group/#");
         DenyWildcardAuthorizer.INSTANCE.authorizeSubscribe(input, output);
 
         verify(output).failAuthorization(SubackReasonCode.NOT_AUTHORIZED, DenyWildcardAuthorizer.REASON_STRING);
     }
 
     @Test
-    public void test_denied_plus_slash() {
-        when(input.getSubscription().getTopicFilter()).thenReturn("+/");
+    public void test_denied_hash() {
+        when(input.getSubscription().getTopicFilter()).thenReturn("/#");
         DenyWildcardAuthorizer.INSTANCE.authorizeSubscribe(input, output);
 
         verify(output).failAuthorization(SubackReasonCode.NOT_AUTHORIZED, DenyWildcardAuthorizer.REASON_STRING);
     }
 
     @Test
-    public void test_denied_hashtag_slash() {
-        when(input.getSubscription().getTopicFilter()).thenReturn("#/");
+    public void test_denied_shared_slash_hash() {
+        when(input.getSubscription().getTopicFilter()).thenReturn("$share/group//#");
         DenyWildcardAuthorizer.INSTANCE.authorizeSubscribe(input, output);
 
         verify(output).failAuthorization(SubackReasonCode.NOT_AUTHORIZED, DenyWildcardAuthorizer.REASON_STRING);
     }
 
     @Test
-    public void test_denied_hashtag_plus() {
-        when(input.getSubscription().getTopicFilter()).thenReturn("#/+");
+    public void test_denied_plus_hash() {
+        when(input.getSubscription().getTopicFilter()).thenReturn("+/#");
         DenyWildcardAuthorizer.INSTANCE.authorizeSubscribe(input, output);
 
         verify(output).failAuthorization(SubackReasonCode.NOT_AUTHORIZED, DenyWildcardAuthorizer.REASON_STRING);
     }
 
     @Test
-    public void test_denied_plus_hashtag() {
-        when(input.getSubscription().getTopicFilter()).thenReturn("+/#");
+    public void test_denied_shared_plus_hash() {
+        when(input.getSubscription().getTopicFilter()).thenReturn("$share/group/+/#");
         DenyWildcardAuthorizer.INSTANCE.authorizeSubscribe(input, output);
 
         verify(output).failAuthorization(SubackReasonCode.NOT_AUTHORIZED, DenyWildcardAuthorizer.REASON_STRING);
     }
 
     @Test
-    public void test_denied_slash_plus() {
-        when(input.getSubscription().getTopicFilter()).thenReturn("/+");
+    public void test_denied_plus_plus() {
+        when(input.getSubscription().getTopicFilter()).thenReturn("+/+");
         DenyWildcardAuthorizer.INSTANCE.authorizeSubscribe(input, output);
 
         verify(output).failAuthorization(SubackReasonCode.NOT_AUTHORIZED, DenyWildcardAuthorizer.REASON_STRING);
     }
 
     @Test
-    public void test_denied_slash_hashtag() {
-        when(input.getSubscription().getTopicFilter()).thenReturn("/#");
+    public void test_denied_shared_plus_plus() {
+        when(input.getSubscription().getTopicFilter()).thenReturn("$share/group/+/+");
         DenyWildcardAuthorizer.INSTANCE.authorizeSubscribe(input, output);
 
         verify(output).failAuthorization(SubackReasonCode.NOT_AUTHORIZED, DenyWildcardAuthorizer.REASON_STRING);
     }
 
+
     @Test
     public void test_success() {
         when(input.getSubscription().getTopicFilter()).thenReturn("topic");
@@ -134,6 +135,30 @@ public void test_success_non_root_hashtag() {
         verify(output).authorizeSuccessfully();
     }
 
+    @Test
+    public void test_success_shared_non_root_wildcard() {
+        when(input.getSubscription().getTopicFilter()).thenReturn("$share/group/topic/#");
+        DenyWildcardAuthorizer.INSTANCE.authorizeSubscribe(input, output);
+
+        verify(output).authorizeSuccessfully();
+    }
+
+    @Test
+    public void test_success_non_root_plus_wildcard() {
+        when(input.getSubscription().getTopicFilter()).thenReturn("+/topic/#");
+        DenyWildcardAuthorizer.INSTANCE.authorizeSubscribe(input, output);
+
+        verify(output).authorizeSuccessfully();
+    }
+
+    @Test
+    public void test_success_shared_non_root_plus_wildcard() {
+        when(input.getSubscription().getTopicFilter()).thenReturn("$share/group/+/topic/#");
+        DenyWildcardAuthorizer.INSTANCE.authorizeSubscribe(input, output);
+
+        verify(output).authorizeSuccessfully();
+    }
+
     @Test
     public void test_success_non_root_plus() {
         when(input.getSubscription().getTopicFilter()).thenReturn("topic/+");