diff --git a/k9mail/src/main/java/com/fsck/k9/search/SearchSpecification.java b/k9mail/src/main/java/com/fsck/k9/search/SearchSpecification.java
index 7c70b832a..17c93b1be 100644
--- a/k9mail/src/main/java/com/fsck/k9/search/SearchSpecification.java
+++ b/k9mail/src/main/java/com/fsck/k9/search/SearchSpecification.java
@@ -138,6 +138,16 @@ public interface SearchSpecification extends Parcelable {
             return false;
         }
 
+        @Override
+        public int hashCode() {
+            int result = 1;
+            result = 31 * result + attribute.hashCode();
+            result = 31 * result + field.hashCode();
+            result = 31 * result + value.hashCode();
+
+            return result;
+        }
+
         @Override
         public int describeContents() {
             return 0;
@@ -164,4 +174,4 @@ public interface SearchSpecification extends Parcelable {
             }
         };
     }
-}
\ No newline at end of file
+}