diff --git a/ACE/protocols/ace/INet/HTTPS_Context.h b/ACE/protocols/ace/INet/HTTPS_Context.h
index 39817884735ba..ca6da44162893 100644
--- a/ACE/protocols/ace/INet/HTTPS_Context.h
+++ b/ACE/protocols/ace/INet/HTTPS_Context.h
@@ -50,7 +50,7 @@ namespace ACE
 
               explicit operator bool () const;
 
-              explicit bool operator ! () const;
+              bool operator ! () const;
 
               ACE_SSL_Context& ssl_context ();
 
diff --git a/ACE/protocols/ace/INet/HTTP_Status.h b/ACE/protocols/ace/INet/HTTP_Status.h
index 0a1368a5edcf7..dfc644d7474dc 100644
--- a/ACE/protocols/ace/INet/HTTP_Status.h
+++ b/ACE/protocols/ace/INet/HTTP_Status.h
@@ -124,7 +124,7 @@ namespace ACE
               explicit operator bool () const;
 
               /// Return true if status code == INVALID
-              explicit bool operator !() const;
+              bool operator !() const;
 
               /// Returns an appropriate reason phrase
               static const ACE_CString& get_reason(Code status);
diff --git a/ACE/protocols/ace/INet/URLBase.h b/ACE/protocols/ace/INet/URLBase.h
index 31fce21e431ac..2ea480dfbd41b 100644
--- a/ACE/protocols/ace/INet/URLBase.h
+++ b/ACE/protocols/ace/INet/URLBase.h
@@ -41,7 +41,7 @@ namespace ACE
               URLStream (const URLStream& url_stream);
               ~URLStream ();
 
-              explicit bool operator ! ();
+              bool operator ! ();
 
               explicit operator bool ();