diff --git a/java/src/com/android/inputmethod/latin/ResearchLogger.java b/java/src/com/android/inputmethod/latin/ResearchLogger.java
index 0694ffe..f39f082 100644
--- a/java/src/com/android/inputmethod/latin/ResearchLogger.java
+++ b/java/src/com/android/inputmethod/latin/ResearchLogger.java
@@ -113,6 +113,7 @@
 
             close();
             mFile = new File(directory, filename);
+            mFile.setReadable(false, false);
             boolean append = true;
             if (mFile.exists() && mFile.lastModified() + LOGFILE_PURGE_INTERVAL <
                     System.currentTimeMillis()) {