diff --git a/src/Egulias/EmailValidator/EmailValidator.php b/src/Egulias/EmailValidator/EmailValidator.php
index d047dec..7e2b65f 100644
--- a/src/Egulias/EmailValidator/EmailValidator.php
+++ b/src/Egulias/EmailValidator/EmailValidator.php
@@ -33,6 +33,7 @@ class EmailValidator
     const ERR_FWS_CRLF_END       = 149;
     const ERR_CR_NO_LF           = 150;
     const ERR_DEPREC_REACHED     = 151;
+    const ERR_UNOPENEDCOMMENT    = 152;
     const RFC5321_TLD             = 9;
     const RFC5321_TLDNUMERIC      = 10;
     const RFC5321_QUOTEDSTRING    = 11;
diff --git a/src/Egulias/EmailValidator/Parser/DomainPart.php b/src/Egulias/EmailValidator/Parser/DomainPart.php
index c4d0cf6..a15bf48 100644
--- a/src/Egulias/EmailValidator/Parser/DomainPart.php
+++ b/src/Egulias/EmailValidator/Parser/DomainPart.php
@@ -4,7 +4,6 @@
 namespace Egulias\EmailValidator\Parser;
 
 use Egulias\EmailValidator\EmailLexer;
-use Egulias\EmailValidator\Parser\Parser;
 use Egulias\EmailValidator\EmailValidator;
 
 class DomainPart extends Parser
@@ -103,8 +102,8 @@ public function checkIPV6Tag($addressLiteral, $maxGroups = 8)
     protected function doParseDomainPart()
     {
         $domain = '';
+        $openedParenthesis = 0;
         do {
-
             $prev = $this->lexer->getPrevious();
 
             if ($this->lexer->token['type'] === EmailLexer::S_SLASH) {
@@ -112,8 +111,19 @@ protected function doParseDomainPart()
             }
 
             if ($this->lexer->token['type'] === EmailLexer::S_OPENPARENTHESIS) {
-                $this->parseComments();
+                $this->parseComments($openedParenthesis);
                 $this->lexer->moveNext();
+                $tmpPrev = $this->lexer->getPrevious();
+                if ($tmpPrev['type'] === EmailLexer::S_CLOSEPARENTHESIS) {
+                    $openedParenthesis--;
+                }
+            }
+            if ($this->lexer->token['type'] === EmailLexer::S_CLOSEPARENTHESIS) {
+                if ($openedParenthesis === 0) {
+                    throw new \InvalidArgumentException('ERR_UNOPENEDCOMMENT');
+                } else {
+                    $openedParenthesis--;
+                }
             }
 
             $this->checkConsecutiveDots();
@@ -180,7 +190,7 @@ protected function doParseDomainLiteral()
             }
 
             if ($this->lexer->isNextToken(EmailLexer::S_CR)) {
-                throw new \InvalidArgumentException("ERR_CR_NO_LF");
+                throw new \InvalidArgumentException('ERR_CR_NO_LF');
             }
             if ($this->lexer->token['type'] === EmailLexer::S_BACKSLASH) {
                 $this->warnings[] = EmailValidator::RFC5322_DOMLIT_OBSDTEXT;
diff --git a/src/Egulias/EmailValidator/Parser/LocalPart.php b/src/Egulias/EmailValidator/Parser/LocalPart.php
index 2f77164..4b768d9 100644
--- a/src/Egulias/EmailValidator/Parser/LocalPart.php
+++ b/src/Egulias/EmailValidator/Parser/LocalPart.php
@@ -4,7 +4,6 @@
 
 use Egulias\EmailValidator\EmailLexer;
 use Egulias\EmailValidator\EmailValidator;
-use \InvalidArgumentException;
 
 class LocalPart extends Parser
 {
@@ -12,9 +11,9 @@ public function parse($localPart)
     {
         $parseDQuote = true;
         $closingQuote = false;
+        $openedParenthesis = 0;
 
         while ($this->lexer->token['type'] !== EmailLexer::S_AT && $this->lexer->token) {
-
             if ($this->lexer->token['type'] === EmailLexer::S_DOT && !$this->lexer->getPrevious()) {
                 throw new \InvalidArgumentException('ERR_DOT_START');
             }
@@ -25,13 +24,19 @@ public function parse($localPart)
             }
 
             if ($this->lexer->token['type'] === EmailLexer::S_OPENPARENTHESIS) {
-                $this->parseComments();
+                $this->parseComments($openedParenthesis);
+            }
+            if ($this->lexer->token['type'] === EmailLexer::S_CLOSEPARENTHESIS) {
+                if ($openedParenthesis === 0) {
+                    throw new \InvalidArgumentException('ERR_UNOPENEDCOMMENT');
+                } else {
+                    $openedParenthesis--;
+                }
             }
 
             $this->checkConsecutiveDots();
 
-            if (
-                $this->lexer->token['type'] === EmailLexer::S_DOT &&
+            if ($this->lexer->token['type'] === EmailLexer::S_DOT &&
                 $this->lexer->isNextToken(EmailLexer::S_AT)
             ) {
                 throw new \InvalidArgumentException('ERR_DOT_END');
@@ -82,7 +87,7 @@ protected function parseDoubleQuote()
             $this->lexer->moveNext();
 
             if (!$this->escaped() && isset($invalid[$this->lexer->token['type']])) {
-                throw new InvalidArgumentException("ERR_EXPECTED_ATEXT");
+                throw new \InvalidArgumentException('ERR_EXPECTED_ATEXT');
             }
         }
 
@@ -90,12 +95,12 @@ protected function parseDoubleQuote()
 
         if ($prev['type'] === EmailLexer::S_BACKSLASH) {
             if (!$this->checkDQUOTE(false)) {
-                throw new \InvalidArgumentException("ERR_UNCLOSED_DQUOTE");
+                throw new \InvalidArgumentException('ERR_UNCLOSED_DQUOTE');
             }
         }
 
         if (!$this->lexer->isNextToken(EmailLexer::S_AT) && $prev['type'] !== EmailLexer::S_BACKSLASH) {
-            throw new \InvalidArgumentException("ERR_EXPECED_AT");
+            throw new \InvalidArgumentException('ERR_EXPECED_AT');
         }
 
         return $parseAgain;
diff --git a/src/Egulias/EmailValidator/Parser/Parser.php b/src/Egulias/EmailValidator/Parser/Parser.php
index b66279e..9d60d97 100644
--- a/src/Egulias/EmailValidator/Parser/Parser.php
+++ b/src/Egulias/EmailValidator/Parser/Parser.php
@@ -20,7 +20,7 @@ public function getWarnings()
         return $this->warnings;
     }
 
-    abstract function parse($str);
+    abstract public function parse($str);
 
     /**
      * validateQuotedPair
@@ -36,14 +36,18 @@ protected function validateQuotedPair()
     }
 
     /**
-     * @return string the the comment
-     * @throws \InvalidArgumentException
+     * @param int $openedParenthesis
+     * @return string the comment
      */
-    protected function parseComments()
+    protected function parseComments(&$openedParenthesis = 0)
     {
+        $openedParenthesis++;
         $this->isUnclosedComment();
         $this->warnings[] = EmailValidator::CFWS_COMMENT;
         while (!$this->lexer->isNextToken(EmailLexer::S_CLOSEPARENTHESIS)) {
+            if ($this->lexer->isNextToken(EmailLexer::S_OPENPARENTHESIS)) {
+                $openedParenthesis++;
+            }
             $this->warnEscaping();
             $this->lexer->moveNext();
         }
@@ -75,11 +79,11 @@ protected function parseFWS()
         $this->checkCRLFInFWS();
 
         if ($this->lexer->token['type'] === EmailLexer::S_CR) {
-            throw new \InvalidArgumentException("ERR_CR_NO_LF");
+            throw new \InvalidArgumentException('ERR_CR_NO_LF');
         }
 
         if ($this->lexer->isNextToken(EmailLexer::GENERIC) && $previous['type']  !== EmailLexer::S_AT) {
-            throw new \InvalidArgumentException("ERR_ATEXT_AFTER_CFWS");
+            throw new \InvalidArgumentException('ERR_ATEXT_AFTER_CFWS');
         }
 
         if ($this->lexer->token['type'] === EmailLexer::S_LF || $this->lexer->token['type'] === EmailLexer::C_NUL) {
@@ -181,10 +185,10 @@ protected function checkCRLFInFWS()
             return;
         }
         if ($this->lexer->isNextToken(EmailLexer::CRLF)) {
-            throw new \InvalidArgumentException("ERR_FWS_CRLF_X2");
+            throw new \InvalidArgumentException('ERR_FWS_CRLF_X2');
         }
         if (!$this->lexer->isNextTokenAny(array(EmailLexer::S_SP, EmailLexer::S_HTAB))) {
-            throw new \InvalidArgumentException("ERR_FWS_CRLF_END");
+            throw new \InvalidArgumentException('ERR_FWS_CRLF_END');
         }
     }
 }
diff --git a/tests/egulias/Tests/EmailValidator/EmailValidatorTest.php b/tests/egulias/Tests/EmailValidator/EmailValidatorTest.php
index 1491df7..03c08d1 100644
--- a/tests/egulias/Tests/EmailValidator/EmailValidatorTest.php
+++ b/tests/egulias/Tests/EmailValidator/EmailValidatorTest.php
@@ -152,6 +152,11 @@ public function getInvalidEmailsWithErrors()
             array(EmailValidator::ERR_DOT_END, 'example@localhost.'),
             array(EmailValidator::ERR_DOT_END, 'example.@example.co.uk'),
             array(EmailValidator::ERR_UNCLOSEDCOMMENT, '(example@localhost'),
+            array(EmailValidator::ERR_UNOPENEDCOMMENT, 'comment)example@localhost'),
+            array(EmailValidator::ERR_UNOPENEDCOMMENT, 'example(comment))@localhost'),
+            array(EmailValidator::ERR_UNOPENEDCOMMENT, 'example@comment)localhost'),
+            array(EmailValidator::ERR_UNOPENEDCOMMENT, 'example@localhost(comment))'),
+            array(EmailValidator::ERR_UNOPENEDCOMMENT, 'example@(comment))example.com'),
             array(EmailValidator::ERR_UNCLOSEDQUOTEDSTR, '"example@localhost'),
             array(EmailValidator::ERR_EXPECTING_ATEXT, 'exa"mple@localhost'),
             //This was the original. But atext is not allowed after \n