diff --git a/cpp/src/phonenumbers/phonenumberutil.h b/cpp/src/phonenumbers/phonenumberutil.h
index a7444607b..2d2dde533 100644
--- a/cpp/src/phonenumbers/phonenumberutil.h
+++ b/cpp/src/phonenumbers/phonenumberutil.h
@@ -397,15 +397,15 @@ class PhoneNumberUtil : public Singleton<PhoneNumberUtil> {
       const string& calling_from,
       string* formatted_number) const;
 
-  // Formats a phone number using the original phone number format that the
-  // number is parsed from. The original format is embedded in the
-  // country_code_source field of the PhoneNumber object passed in. If such
-  // information is missing, the number will be formatted into the NATIONAL
-  // format by default. When we don't have a formatting pattern for the number,
-  // the method returns the raw input when it is available.
-  //
-  // Note this method guarantees no digit will be inserted, removed or modified
-  // as a result of formatting.
+  // Formats a phone number using the original phone number format (e.g.
+  // INTERNATIONAL or NATIONAL) that the number is parsed from, provided that
+  // the number has been parsed with ParseAndKeepRawInput. Otherwise the number
+  // will be formatted in NATIONAL format. The original format is embedded in
+  // the country_code_source field of the PhoneNumber object passed in, which is
+  // only set when parsing keeps the raw input. When we don't have a formatting
+  // pattern for the number, the method falls back to returning the raw input.
+  // When the number is an invalid number, the method returns the raw input when
+  // it is available.
   void FormatInOriginalFormat(const PhoneNumber& number,
                               const string& region_calling_from,
                               string* formatted_number) const;
diff --git a/java/libphonenumber/src/com/google/i18n/phonenumbers/PhoneNumberUtil.java b/java/libphonenumber/src/com/google/i18n/phonenumbers/PhoneNumberUtil.java
index 677110d32..cea2b3c70 100644
--- a/java/libphonenumber/src/com/google/i18n/phonenumbers/PhoneNumberUtil.java
+++ b/java/libphonenumber/src/com/google/i18n/phonenumbers/PhoneNumberUtil.java
@@ -1615,19 +1615,21 @@ public class PhoneNumberUtil {
   }
 
   /**
-   * Formats a phone number using the original phone number format that the number is parsed from.
-   * The original format is embedded in the country_code_source field of the PhoneNumber object
-   * passed in. If such information is missing, the number will be formatted into the NATIONAL
-   * format by default. When we don't have a formatting pattern for the number, the method returns
-   * the raw input when it is available.
+   * Formats a phone number using the original phone number format (e.g. INTERNATIONAL or NATIONAL)
+   * that the number is parsed from, provided that the number has been parsed with {@link
+   * parseAndKeepRawInput}. Otherwise the number will be formatted in NATIONAL format.
    *
-   * Note this method guarantees no digit will be inserted, removed or modified as a result of
+   * <p>The original format is embedded in the country_code_source field of the PhoneNumber object
+   * passed in, which is only set when parsing keeps the raw input. When we don't have a formatting
+   * pattern for the number, the method falls back to returning the raw input.
+   *
+   * <p>Note this method guarantees no digit will be inserted, removed or modified as a result of
    * formatting.
    *
-   * @param number  the phone number that needs to be formatted in its original number format
-   * @param regionCallingFrom  the region whose IDD needs to be prefixed if the original number
-   *     has one
-   * @return  the formatted phone number in its original number format
+   * @param number the phone number that needs to be formatted in its original number format
+   * @param regionCallingFrom the region whose IDD needs to be prefixed if the original number has
+   *     one
+   * @return the formatted phone number in its original number format
    */
   public String formatInOriginalFormat(PhoneNumber number, String regionCallingFrom) {
     if (number.hasRawInput() && !hasFormattingPatternForNumber(number)) {