diff --git a/java/src/com/android/inputmethod/latin/ExpandableBinaryDictionary.java b/java/src/com/android/inputmethod/latin/ExpandableBinaryDictionary.java
index def978e4b..b93c17f11 100644
--- a/java/src/com/android/inputmethod/latin/ExpandableBinaryDictionary.java
+++ b/java/src/com/android/inputmethod/latin/ExpandableBinaryDictionary.java
@@ -21,6 +21,7 @@ import android.util.Log;
 import com.android.inputmethod.keyboard.ProximityInfo;
 import com.android.inputmethod.latin.SuggestedWords.SuggestedWordInfo;
 import com.android.inputmethod.latin.makedict.BinaryDictInputOutput;
+import com.android.inputmethod.latin.makedict.FormatSpec;
 import com.android.inputmethod.latin.makedict.FusionDictionary;
 import com.android.inputmethod.latin.makedict.FusionDictionary.Node;
 import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
@@ -90,8 +91,8 @@ abstract public class ExpandableBinaryDictionary extends Dictionary {
     private final DictionaryController mLocalDictionaryController = new DictionaryController();
 
     private static final int BINARY_DICT_VERSION = 1;
-    private static final BinaryDictInputOutput.FormatOptions FORMAT_OPTIONS =
-            new BinaryDictInputOutput.FormatOptions(BINARY_DICT_VERSION);
+    private static final FormatSpec.FormatOptions FORMAT_OPTIONS =
+            new FormatSpec.FormatOptions(BINARY_DICT_VERSION);
 
     /**
      * Abstract method for loading the unigrams and bigrams of a given dictionary in a background
diff --git a/java/src/com/android/inputmethod/latin/UserHistoryDictIOUtils.java b/java/src/com/android/inputmethod/latin/UserHistoryDictIOUtils.java
index 1f5f1f7e6..550e4e58b 100644
--- a/java/src/com/android/inputmethod/latin/UserHistoryDictIOUtils.java
+++ b/java/src/com/android/inputmethod/latin/UserHistoryDictIOUtils.java
@@ -19,8 +19,8 @@ package com.android.inputmethod.latin;
 import android.util.Log;
 
 import com.android.inputmethod.latin.makedict.BinaryDictInputOutput;
-import com.android.inputmethod.latin.makedict.BinaryDictInputOutput.FormatOptions;
 import com.android.inputmethod.latin.makedict.BinaryDictInputOutput.FusionDictionaryBufferInterface;
+import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
 import com.android.inputmethod.latin.makedict.FusionDictionary;
 import com.android.inputmethod.latin.makedict.FusionDictionary.Node;
 import com.android.inputmethod.latin.makedict.PendingAttribute;
diff --git a/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java b/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
index d268265c3..ef10f7270 100644
--- a/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
+++ b/java/src/com/android/inputmethod/latin/makedict/BinaryDictInputOutput.java
@@ -16,6 +16,8 @@
 
 package com.android.inputmethod.latin.makedict;
 
+import com.android.inputmethod.latin.makedict.FormatSpec.FileHeader;
+import com.android.inputmethod.latin.makedict.FormatSpec.FormatOptions;
 import com.android.inputmethod.latin.makedict.FusionDictionary.CharGroup;
 import com.android.inputmethod.latin.makedict.FusionDictionary.DictionaryOptions;
 import com.android.inputmethod.latin.makedict.FusionDictionary.Node;
@@ -107,40 +109,6 @@ public class BinaryDictInputOutput {
         }
     }
 
-    /**
-     * Options about file format.
-     */
-    public static class FormatOptions {
-        public final int mVersion;
-        public final boolean mHasParentAddress;
-        public FormatOptions(final int version) {
-            this(version, false);
-        }
-        public FormatOptions(final int version, final boolean hasParentAddress) {
-            mVersion = version;
-            if (version < FormatSpec.FIRST_VERSION_WITH_PARENT_ADDRESS && hasParentAddress) {
-                throw new RuntimeException("Parent addresses are only supported with versions "
-                        + FormatSpec.FIRST_VERSION_WITH_PARENT_ADDRESS + " and ulterior.");
-            }
-            mHasParentAddress = hasParentAddress;
-        }
-    }
-
-    /**
-     * Class representing file header.
-     */
-    private static final class FileHeader {
-        public final int mHeaderSize;
-        public final DictionaryOptions mDictionaryOptions;
-        public final FormatOptions mFormatOptions;
-        public FileHeader(final int headerSize, final DictionaryOptions dictionaryOptions,
-                final FormatOptions formatOptions) {
-            mHeaderSize = headerSize;
-            mDictionaryOptions = dictionaryOptions;
-            mFormatOptions = formatOptions;
-        }
-    }
-
     /**
      * A class grouping utility function for our specific character encoding.
      */
diff --git a/java/src/com/android/inputmethod/latin/makedict/FormatSpec.java b/java/src/com/android/inputmethod/latin/makedict/FormatSpec.java
index 1e2e93d90..1707ccc39 100644
--- a/java/src/com/android/inputmethod/latin/makedict/FormatSpec.java
+++ b/java/src/com/android/inputmethod/latin/makedict/FormatSpec.java
@@ -17,6 +17,7 @@
 package com.android.inputmethod.latin.makedict;
 
 import com.android.inputmethod.latin.Constants;
+import com.android.inputmethod.latin.makedict.FusionDictionary.DictionaryOptions;
 
 /**
  * Dictionary File Format Specification.
@@ -194,6 +195,40 @@ public final class FormatSpec {
     static final int MAX_TERMINAL_FREQUENCY = 255;
     static final int MAX_BIGRAM_FREQUENCY = 15;
 
+    /**
+     * Options about file format.
+     */
+    public static class FormatOptions {
+        public final int mVersion;
+        public final boolean mHasParentAddress;
+        public FormatOptions(final int version) {
+            this(version, false);
+        }
+        public FormatOptions(final int version, final boolean hasParentAddress) {
+            mVersion = version;
+            if (version < FormatSpec.FIRST_VERSION_WITH_PARENT_ADDRESS && hasParentAddress) {
+                throw new RuntimeException("Parent addresses are only supported with versions "
+                        + FormatSpec.FIRST_VERSION_WITH_PARENT_ADDRESS + " and ulterior.");
+            }
+            mHasParentAddress = hasParentAddress;
+        }
+    }
+
+    /**
+     * Class representing file header.
+     */
+    static final class FileHeader {
+        public final int mHeaderSize;
+        public final DictionaryOptions mDictionaryOptions;
+        public final FormatOptions mFormatOptions;
+        public FileHeader(final int headerSize, final DictionaryOptions dictionaryOptions,
+                final FormatOptions formatOptions) {
+            mHeaderSize = headerSize;
+            mDictionaryOptions = dictionaryOptions;
+            mFormatOptions = formatOptions;
+        }
+    }
+
     private FormatSpec() {
         // This utility class is not publicly instantiable.
     }
diff --git a/tests/src/com/android/inputmethod/latin/UserHistoryDictIOUtilsTests.java b/tests/src/com/android/inputmethod/latin/UserHistoryDictIOUtilsTests.java
index 5fa740f6e..70f916c1a 100644
--- a/tests/src/com/android/inputmethod/latin/UserHistoryDictIOUtilsTests.java
+++ b/tests/src/com/android/inputmethod/latin/UserHistoryDictIOUtilsTests.java
@@ -19,6 +19,7 @@ package com.android.inputmethod.latin;
 import com.android.inputmethod.latin.UserHistoryDictIOUtils.BigramDictionaryInterface;
 import com.android.inputmethod.latin.UserHistoryDictIOUtils.OnAddWordListener;
 import com.android.inputmethod.latin.makedict.BinaryDictInputOutput;
+import com.android.inputmethod.latin.makedict.FormatSpec;
 import com.android.inputmethod.latin.makedict.FusionDictionary;
 import com.android.inputmethod.latin.makedict.FusionDictionary.CharGroup;
 
@@ -45,8 +46,7 @@ public class UserHistoryDictIOUtilsTests extends AndroidTestCase
     private static final int UNIGRAM_FREQUENCY = 50;
     private static final int BIGRAM_FREQUENCY = 100;
     private static final ArrayList<String> NOT_HAVE_BIGRAM = new ArrayList<String>();
-    private static final BinaryDictInputOutput.FormatOptions FORMAT_OPTIONS =
-            new BinaryDictInputOutput.FormatOptions(2);
+    private static final FormatSpec.FormatOptions FORMAT_OPTIONS = new FormatSpec.FormatOptions(2);
 
     /**
      * Return same frequency for all words and bigrams
diff --git a/tests/src/com/android/inputmethod/latin/makedict/BinaryDictIOTests.java b/tests/src/com/android/inputmethod/latin/makedict/BinaryDictIOTests.java
index 523287b48..5d9c229e3 100644
--- a/tests/src/com/android/inputmethod/latin/makedict/BinaryDictIOTests.java
+++ b/tests/src/com/android/inputmethod/latin/makedict/BinaryDictIOTests.java
@@ -19,6 +19,7 @@ package com.android.inputmethod.latin.makedict;
 import com.android.inputmethod.latin.CollectionUtils;
 import com.android.inputmethod.latin.UserHistoryDictIOUtils;
 import com.android.inputmethod.latin.makedict.BinaryDictInputOutput.FusionDictionaryBufferInterface;
+import com.android.inputmethod.latin.makedict.FormatSpec;
 import com.android.inputmethod.latin.makedict.FusionDictionary.CharGroup;
 import com.android.inputmethod.latin.makedict.FusionDictionary.Node;
 import com.android.inputmethod.latin.makedict.FusionDictionary.WeightedString;
@@ -62,8 +63,7 @@ public class BinaryDictIOTests extends AndroidTestCase {
     private static final SparseArray<List<Integer>> sChainBigrams =
             CollectionUtils.newSparseArray();
 
-    private static final BinaryDictInputOutput.FormatOptions VERSION2 =
-            new BinaryDictInputOutput.FormatOptions(2);
+    private static final FormatSpec.FormatOptions VERSION2 = new FormatSpec.FormatOptions(2);
 
     private static final String[] CHARACTERS = {
         "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m",
diff --git a/tools/dicttool/src/android/inputmethod/latin/dicttool/DictionaryMaker.java b/tools/dicttool/src/android/inputmethod/latin/dicttool/DictionaryMaker.java
index 7cd4564f3..a6137706e 100644
--- a/tools/dicttool/src/android/inputmethod/latin/dicttool/DictionaryMaker.java
+++ b/tools/dicttool/src/android/inputmethod/latin/dicttool/DictionaryMaker.java
@@ -17,6 +17,7 @@
 package com.android.inputmethod.latin.dicttool;
 
 import com.android.inputmethod.latin.makedict.BinaryDictInputOutput;
+import com.android.inputmethod.latin.makedict.FormatSpec;
 import com.android.inputmethod.latin.makedict.FusionDictionary;
 import com.android.inputmethod.latin.makedict.MakedictLog;
 import com.android.inputmethod.latin.makedict.UnsupportedFormatException;
@@ -311,8 +312,7 @@ public class DictionaryMaker {
             final FusionDictionary dict, final int version)
             throws FileNotFoundException, IOException, UnsupportedFormatException {
         final File outputFile = new File(outputFilename);
-        final BinaryDictInputOutput.FormatOptions formatOptions =
-                new BinaryDictInputOutput.FormatOptions(version);
+        final FormatSpec.FormatOptions formatOptions = new FormatSpec.FormatOptions(version);
         BinaryDictInputOutput.writeDictionaryBinary(new FileOutputStream(outputFilename), dict,
                 formatOptions);
     }