diff --git a/lib/valid_email2/address.rb b/lib/valid_email2/address.rb
index 38cfd02..0a7a7b8 100644
--- a/lib/valid_email2/address.rb
+++ b/lib/valid_email2/address.rb
@@ -8,7 +8,7 @@ module ValidEmail2
   class Address
     attr_accessor :address
 
-    PROHIBITED_DOMAIN_CHARACTERS_REGEX = /[+!_\/\s'#`]/
+    PROHIBITED_DOMAIN_CHARACTERS_REGEX = /[+!_\/\s'#`|]/
     DEFAULT_RECIPIENT_DELIMITER = '+'
     DOT_DELIMITER = '.'
     HYPHEN_DELIMITER = '-'
diff --git a/spec/address_spec.rb b/spec/address_spec.rb
index 404677b..fe9820a 100644
--- a/spec/address_spec.rb
+++ b/spec/address_spec.rb
@@ -38,6 +38,11 @@
       expect(address.valid?).to be false
     end
 
+    it "is invalid if email contains a pipe" do
+      address = described_class.new("foo@gmai|.com")
+      expect(address.valid?).to be false
+    end
+
     it "is invalid if it contains Japanese characters" do
       address = described_class.new("あいうえお@example.com")
       expect(address.valid?).to be false