diff --git a/java/proguard.flags b/java/proguard.flags
index 829a096..2023075 100644
--- a/java/proguard.flags
+++ b/java/proguard.flags
@@ -5,4 +5,11 @@
 
 -keep class com.android.inputmethod.latin.Suggest {
   <init>(...);
+  com.android.inputmethod.latin.SuggestedWords getSuggestions(...);
+}
+
+-keep class com.android.inputmethod.latin.UserBigramDictionary {
+  void setDatabaseMax(int);
+  void setDatabaseDelete(int);
+  void waitUntilUpdateDBDone();
 }