diff --git a/app/src/main/java/org/thoughtcrime/securesms/database/GroupDatabase.java b/app/src/main/java/org/thoughtcrime/securesms/database/GroupDatabase.java
index 82b00a16c3..09bea00ad8 100644
--- a/app/src/main/java/org/thoughtcrime/securesms/database/GroupDatabase.java
+++ b/app/src/main/java/org/thoughtcrime/securesms/database/GroupDatabase.java
@@ -27,10 +27,10 @@ import org.thoughtcrime.securesms.recipients.Recipient;
 import org.thoughtcrime.securesms.recipients.RecipientId;
 import org.thoughtcrime.securesms.util.Util;
 import org.whispersystems.libsignal.util.guava.Optional;
+import org.whispersystems.signalservice.api.groupsv2.DecryptedGroupUtil;
 import org.whispersystems.signalservice.api.messages.SignalServiceAttachmentPointer;
 import org.whispersystems.signalservice.api.push.SignalServiceAddress;
 import org.whispersystems.signalservice.api.util.UuidUtil;
-import org.whispersystems.signalservice.api.groupsv2.DecryptedGroupUtil;
 
 import java.io.Closeable;
 import java.security.SecureRandom;
@@ -200,9 +200,9 @@ public final class GroupDatabase extends Database {
 
     try (Cursor cursor = database.query(table, null, query, args, null, null, orderBy)) {
       while (cursor != null && cursor.moveToNext()) {
-        List<String> members = Util.split(cursor.getString(cursor.getColumnIndexOrThrow(MEMBERS)), ",");
+        String serializedMembers = cursor.getString(cursor.getColumnIndexOrThrow(MEMBERS));
 
-        if (members.contains(recipientId.serialize())) {
+        if (RecipientId.serializedListContains(serializedMembers, recipientId)) {
           groups.add(new Reader(cursor).getCurrent());
         }
       }
@@ -452,6 +452,23 @@ public final class GroupDatabase extends Database {
     database.update(TABLE_NAME, values, GROUP_ID + " = ?", new String[] {groupId.toString()});
   }
 
+  @WorkerThread
+  public boolean isCurrentMember(@NonNull GroupId.Push groupId, @NonNull RecipientId recipientId) {
+    SQLiteDatabase database = databaseHelper.getReadableDatabase();
+
+    try (Cursor cursor = database.query(TABLE_NAME, new String[] {MEMBERS},
+                                        GROUP_ID + " = ?", new String[] {groupId.toString()},
+                                        null, null, null))
+    {
+      if (cursor.moveToNext()) {
+        String serializedMembers = cursor.getString(cursor.getColumnIndexOrThrow(MEMBERS));
+        return RecipientId.serializedListContains(serializedMembers, recipientId);
+      } else {
+        return false;
+      }
+    }
+  }
+
   private static String serializeV2GroupMembers(@NonNull Context context, @NonNull DecryptedGroup decryptedGroup) {
     List<RecipientId> groupMembers  = new ArrayList<>(decryptedGroup.getMembersCount());
 
diff --git a/app/src/main/java/org/thoughtcrime/securesms/groups/GroupId.java b/app/src/main/java/org/thoughtcrime/securesms/groups/GroupId.java
index 9048e65cf6..42cea40ea3 100644
--- a/app/src/main/java/org/thoughtcrime/securesms/groups/GroupId.java
+++ b/app/src/main/java/org/thoughtcrime/securesms/groups/GroupId.java
@@ -19,7 +19,6 @@ public abstract class GroupId {
   private static final int    MMS_BYTE_LENGTH             = 16;
   private static final int    V1_MMS_BYTE_LENGTH          = 16;
   private static final int    V2_BYTE_LENGTH              = GroupIdentifier.SIZE;
-  private static final int    V2_ENCODED_LENGTH           = ENCODED_SIGNAL_GROUP_PREFIX.length() + V2_BYTE_LENGTH * 2;
 
   private final String encodedId;
 
@@ -63,6 +62,10 @@ public abstract class GroupId {
                                .getGroupIdentifier());
   }
 
+  public static GroupId.Push push(byte[] bytes) {
+    return bytes.length == V2_BYTE_LENGTH ? v2(bytes) : v1(bytes);
+  }
+
   public static @NonNull GroupId parse(@NonNull String encodedGroupId) {
     try {
       if (!isEncodedGroup(encodedGroupId)) {
@@ -71,10 +74,7 @@ public abstract class GroupId {
 
       byte[] bytes = extractDecodedId(encodedGroupId);
 
-           if (encodedGroupId.startsWith(ENCODED_MMS_GROUP_PREFIX)) return mms(bytes);
-      else if (encodedGroupId.length() == V2_ENCODED_LENGTH)        return v2(bytes);
-      else                                                          return v1(bytes);
-
+      return encodedGroupId.startsWith(ENCODED_MMS_GROUP_PREFIX) ? mms(bytes) : push(bytes);
     } catch (IOException e) {
       throw new AssertionError(e);
     }
diff --git a/app/src/main/java/org/thoughtcrime/securesms/jobs/PushProcessMessageJob.java b/app/src/main/java/org/thoughtcrime/securesms/jobs/PushProcessMessageJob.java
index daf53f6c35..6bf6106b77 100644
--- a/app/src/main/java/org/thoughtcrime/securesms/jobs/PushProcessMessageJob.java
+++ b/app/src/main/java/org/thoughtcrime/securesms/jobs/PushProcessMessageJob.java
@@ -1324,8 +1324,14 @@ public final class PushProcessMessageJob extends BaseJob {
     long threadId;
 
     if (typingMessage.getGroupId().isPresent()) {
-      RecipientId recipientId  = DatabaseFactory.getRecipientDatabase(context).getOrInsertFromGroupId(GroupId.v1(typingMessage.getGroupId().get()));
-      Recipient groupRecipient = Recipient.resolved(recipientId);
+      GroupId.Push groupId = GroupId.push(typingMessage.getGroupId().get());
+
+      if (!DatabaseFactory.getGroupDatabase(context).isCurrentMember(groupId, author.getId())) {
+        Log.w(TAG, "Seen typing indicator for non-member");
+        return;
+      }
+
+      Recipient groupRecipient = Recipient.externalGroup(context, groupId);
 
       threadId = DatabaseFactory.getThreadDatabase(context).getThreadIdFor(groupRecipient);
     } else {
diff --git a/app/src/main/java/org/thoughtcrime/securesms/recipients/RecipientId.java b/app/src/main/java/org/thoughtcrime/securesms/recipients/RecipientId.java
index 092ee8f022..aa96ade38e 100644
--- a/app/src/main/java/org/thoughtcrime/securesms/recipients/RecipientId.java
+++ b/app/src/main/java/org/thoughtcrime/securesms/recipients/RecipientId.java
@@ -12,6 +12,7 @@ import org.thoughtcrime.securesms.util.Util;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.regex.Pattern;
 
 public class RecipientId implements Parcelable, Comparable<RecipientId> {
 
@@ -62,6 +63,12 @@ public class RecipientId implements Parcelable, Comparable<RecipientId> {
     return out;
   }
 
+  public static boolean serializedListContains(@NonNull String serialized, @NonNull RecipientId recipientId) {
+    return Pattern.compile("\\b" + recipientId.serialize() + "\\b")
+                  .matcher(serialized)
+                  .find();
+  }
+
   public boolean isUnknown() {
     return id == UNKNOWN_ID;
   }
diff --git a/app/src/main/java/org/thoughtcrime/securesms/util/DelimiterUtil.java b/app/src/main/java/org/thoughtcrime/securesms/util/DelimiterUtil.java
index a338cc9f79..bf27f659cd 100644
--- a/app/src/main/java/org/thoughtcrime/securesms/util/DelimiterUtil.java
+++ b/app/src/main/java/org/thoughtcrime/securesms/util/DelimiterUtil.java
@@ -1,8 +1,6 @@
 package org.thoughtcrime.securesms.util;
 
 
-import android.text.TextUtils;
-
 import java.util.regex.Pattern;
 
 public class DelimiterUtil {
@@ -16,7 +14,7 @@ public class DelimiterUtil {
   }
 
   public static String[] split(String value, char delimiter) {
-    if (TextUtils.isEmpty(value)) {
+    if (value == null || value.length() == 0) {
       return new String[0];
     } else {
       String regex = "(?<!\\\\)" + Pattern.quote(delimiter + "");
diff --git a/app/src/test/java/org/thoughtcrime/securesms/groups/GroupIdTest.java b/app/src/test/java/org/thoughtcrime/securesms/groups/GroupIdTest.java
index b835ddee03..9448ad5631 100644
--- a/app/src/test/java/org/thoughtcrime/securesms/groups/GroupIdTest.java
+++ b/app/src/test/java/org/thoughtcrime/securesms/groups/GroupIdTest.java
@@ -281,4 +281,18 @@ public final class GroupIdTest {
     assertEquals("__textsecure_group__!090a0b0c0d0e0f000102030405060708", v1.toString());
     assertTrue(v1.isV1());
   }
+
+  @Test
+  public void parse_bytes_to_v1_via_push() {
+    GroupId.V1 v1 = GroupId.push(new byte[]{ 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8 }).requireV1();
+
+    assertEquals("__textsecure_group__!090a0b0c0d0e0f000102030405060708", v1.toString());
+  }
+
+  @Test
+  public void parse_bytes_to_v2_via_by_push() {
+    GroupId.V2 v2 = GroupId.push(new byte[]{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 }).requireV2();
+
+    assertEquals("__textsecure_group__!000102030405060708090a0b0c0d0e0f000102030405060708090a0b0c0d0e0f", v2.toString());
+  }
 }
diff --git a/app/src/test/java/org/thoughtcrime/securesms/recipients/RecipientIdSerializationTest.java b/app/src/test/java/org/thoughtcrime/securesms/recipients/RecipientIdSerializationTest.java
new file mode 100644
index 0000000000..325ac75f13
--- /dev/null
+++ b/app/src/test/java/org/thoughtcrime/securesms/recipients/RecipientIdSerializationTest.java
@@ -0,0 +1,94 @@
+package org.thoughtcrime.securesms.recipients;
+
+import org.junit.Test;
+
+import static java.util.Arrays.asList;
+import static java.util.Collections.emptyList;
+import static java.util.Collections.singletonList;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+public final class RecipientIdSerializationTest {
+
+  @Test
+  public void toSerializedList_empty() {
+    assertEquals("", RecipientId.toSerializedList(emptyList()));
+  }
+
+  @Test
+  public void toSerializedList_one_item() {
+    assertEquals("123", RecipientId.toSerializedList(singletonList(RecipientId.from(123))));
+  }
+
+  @Test
+  public void toSerializedList_two_items() {
+    assertEquals("123,987", RecipientId.toSerializedList(asList(RecipientId.from(123), RecipientId.from("987"))));
+  }
+
+  @Test
+  public void fromSerializedList_empty() {
+    assertThat(RecipientId.fromSerializedList(""), is(emptyList()));
+  }
+
+  @Test
+  public void fromSerializedList_one_item() {
+    assertThat(RecipientId.fromSerializedList("123"), is(singletonList(RecipientId.from(123))));
+  }
+
+  @Test
+  public void fromSerializedList_two_items() {
+    assertThat(RecipientId.fromSerializedList("123,456"), is(asList(RecipientId.from(123), RecipientId.from(456))));
+  }
+
+  @Test
+  public void serializedListContains_empty_list_does_not_contain_item() {
+    assertFalse(RecipientId.serializedListContains("", RecipientId.from(456)));
+  }
+
+  @Test
+  public void serializedListContains_single_list_does_not_contain_item() {
+    assertFalse(RecipientId.serializedListContains("123", RecipientId.from(456)));
+  }
+
+  @Test
+  public void serializedListContains_single_list_does_contain_item() {
+    assertTrue(RecipientId.serializedListContains("456", RecipientId.from(456)));
+  }
+
+  @Test
+  public void serializedListContains_double_list_does_contain_item_in_first_position() {
+    assertTrue(RecipientId.serializedListContains("456,123", RecipientId.from(456)));
+  }
+
+  @Test
+  public void serializedListContains_double_list_does_contain_item_in_second_position() {
+    assertTrue(RecipientId.serializedListContains("123,456", RecipientId.from(456)));
+  }
+
+  @Test
+  public void serializedListContains_single_list_does_not_contain_item_due_to_extra_digit_at_start() {
+    assertFalse(RecipientId.serializedListContains("1456", RecipientId.from(456)));
+  }
+
+  @Test
+  public void serializedListContains_single_list_does_not_contain_item_due_to_extra_digit_at_end() {
+    assertFalse(RecipientId.serializedListContains("4561", RecipientId.from(456)));
+  }
+
+  @Test
+  public void serializedListContains_find_all_items_in_triple_list() {
+    assertTrue(RecipientId.serializedListContains("11,12,13", RecipientId.from(11)));
+    assertTrue(RecipientId.serializedListContains("11,12,13", RecipientId.from(12)));
+    assertTrue(RecipientId.serializedListContains("11,12,13", RecipientId.from(13)));
+  }
+
+  @Test
+  public void serializedListContains_cant_find_similar_items_in_triple_list() {
+    assertFalse(RecipientId.serializedListContains("11,12,13", RecipientId.from(1)));
+    assertFalse(RecipientId.serializedListContains("11,12,13", RecipientId.from(2)));
+    assertFalse(RecipientId.serializedListContains("11,12,13", RecipientId.from(3)));
+  }
+}