diff --git a/gts/Web.config b/gts/Web.config
index e0065ad8..14ece979 100644
--- a/gts/Web.config
+++ b/gts/Web.config
@@ -12,6 +12,10 @@
          providerName="MySql.Data.MySqlClient" />
   </connectionStrings>
 
+  <appSettings>
+    <add key="AllowedProxies" value="::1,127.0.0.1,178.62.43.212,195.201.236.139,172.104.88.237" />
+  </appSettings>
+
   <system.web>
     <compilation debug="true" targetFramework="4.0" />
 <!--
diff --git a/gts/gts.csproj b/gts/gts.csproj
index 83a8b553..43400723 100644
--- a/gts/gts.csproj
+++ b/gts/gts.csproj
@@ -122,6 +122,7 @@
     </Compile>
     <Compile Include="src\AppStateHelper.cs" />
     <Compile Include="src\FakeOpponentGenerator4.cs" />
+    <Compile Include="src\IpAddressHelper.cs" />
     <Compile Include="syachi2ds.ashx.cs">
       <DependentUpon>syachi2ds.ashx</DependentUpon>
     </Compile>
diff --git a/gts/pokemondpds.ashx.cs b/gts/pokemondpds.ashx.cs
index 15cab729..6c9733d4 100644
--- a/gts/pokemondpds.ashx.cs
+++ b/gts/pokemondpds.ashx.cs
@@ -56,7 +56,7 @@ namespace PkmnFoundations.GTS
 #endif
                         byte[] profileBinary = new byte[100];
                         Array.Copy(data, 0, profileBinary, 0, 100);
-                        TrainerProfile4 profile = new TrainerProfile4(pid, profileBinary);
+                        TrainerProfile4 profile = new TrainerProfile4(pid, profileBinary, IpAddressHelper.GetIpAddress(context.Request));
                         Database.Instance.GamestatsSetProfile4(profile);
 #if !DEBUG
                     }
@@ -124,7 +124,7 @@ namespace PkmnFoundations.GTS
                     // todo: find out the meaning of this request.
                     // is it simply done to check whether the GTS is online?
 
-                    Database.Instance.GamestatsBumpProfile4(pid);
+                    Database.Instance.GamestatsBumpProfile4(pid, IpAddressHelper.GetIpAddress(context.Request));
                     response.Write(new byte[] { 0x01, 0x00 }, 0, 2);
                     break;
 
@@ -510,7 +510,7 @@ namespace PkmnFoundations.GTS
                     SessionManager.Remove(session);
 
                     // Probably an availability/status code.
-                    Database.Instance.GamestatsBumpProfile4(pid);
+                    Database.Instance.GamestatsBumpProfile4(pid, IpAddressHelper.GetIpAddress(context.Request));
 
                     // Response codes:
                     // 0x00: BSOD
diff --git a/gts/src/IpAddressHelper.cs b/gts/src/IpAddressHelper.cs
new file mode 100644
index 00000000..d8ca9419
--- /dev/null
+++ b/gts/src/IpAddressHelper.cs
@@ -0,0 +1,36 @@
+using System;
+using System.Collections.Generic;
+using System.Configuration;
+using System.Linq;
+using System.Web;
+
+namespace PkmnFoundations.GTS
+{
+    public static class IpAddressHelper
+    {
+        public static string GetIpAddress(HttpRequest request)
+        {
+            var allowedProxies = ConfigurationManager.AppSettings["AllowedProxies"].Split(',').Select(s => s.Trim());
+            string hostAddress = RemovePort(request.UserHostAddress.Trim());
+            
+            if (!allowedProxies.Contains(hostAddress)) return hostAddress; // return real IP if not a blessed proxy
+
+            var xForwardedFor = request.Headers["X-Forwarded-For"].Split(',').Select(s => RemovePort(s.Trim()));
+            foreach (string s in xForwardedFor.Reverse())
+            {
+                if (!allowedProxies.Contains(s)) return s; // return LAST IP in the proxy chain that's not trusted. (everything coming earlier could be spoofed)
+            }
+
+            // these conditions can only happen if the real user is at a blessed proxy IP address. (probably localhost)
+            return xForwardedFor.FirstOrDefault() ?? hostAddress;
+        }
+
+        private static string RemovePort(string ip)
+        {
+            if (ip.Contains(':') && ip.Contains('.'))
+                return ip.Substring(0, ip.IndexOf(':'));
+            else
+                return ip;
+        }
+    }
+}
diff --git a/gts/syachi2ds.ashx.cs b/gts/syachi2ds.ashx.cs
index 7ddf6453..6317fda1 100644
--- a/gts/syachi2ds.ashx.cs
+++ b/gts/syachi2ds.ashx.cs
@@ -56,7 +56,7 @@ namespace PkmnFoundations.GTS
                     // Specifically, email, notification status, and the two secrets appear to always be 0.
                         byte[] profileBinary = new byte[100];
                         Array.Copy(request, 0, profileBinary, 0, 100);
-                        TrainerProfile5 profile = new TrainerProfile5(pid, profileBinary);
+                        TrainerProfile5 profile = new TrainerProfile5(pid, profileBinary, IpAddressHelper.GetIpAddress(context.Request));
                         Database.Instance.GamestatsSetProfile5(profile);
 #if !DEBUG
                     }
diff --git a/library/Data/DataMysql.cs b/library/Data/DataMysql.cs
index 25fad9dd..ae277ef7 100644
--- a/library/Data/DataMysql.cs
+++ b/library/Data/DataMysql.cs
@@ -1056,12 +1056,12 @@ namespace PkmnFoundations.Data
         #endregion
 
         #region Other Gamestats 4
-        public override bool GamestatsBumpProfile4(int pid)
+        public override bool GamestatsBumpProfile4(int pid, string ip_address)
         {
-            return WithTransaction(tran => GamestatsBumpProfile4(tran, pid));
+            return WithTransaction(tran => GamestatsBumpProfile4(tran, pid, ip_address));
         }
 
-        public bool GamestatsBumpProfile4(MySqlTransaction tran, int pid)
+        public bool GamestatsBumpProfile4(MySqlTransaction tran, int pid, string ip_address)
         {
             bool exists = Convert.ToSByte(tran.ExecuteScalar("SELECT EXISTS(SELECT * FROM GtsProfiles4 WHERE pid = @pid)", 
                 new MySqlParameter("@pid", pid))) != 0;
@@ -1069,13 +1069,18 @@ namespace PkmnFoundations.Data
             if (exists)
             {
                 return tran.ExecuteNonQuery("UPDATE GtsProfiles4 SET " +
-                    "TimeUpdated = UTC_TIMESTAMP() WHERE pid = @pid", new MySqlParameter("@pid", pid)) > 0;
+                    "TimeUpdated = UTC_TIMESTAMP(), IpAddress = @ip_address " +
+                    "WHERE pid = @pid", 
+                    new MySqlParameter("@ip_address", ip_address),
+                    new MySqlParameter("@pid", pid)) > 0;
             }
             else
             {
                 return tran.ExecuteNonQuery("INSERT INTO GtsProfiles4 " +
-                    "(pid, TimeAdded, TimeUpdated) VALUES (@pid, UTC_TIMESTAMP(), " +
-                    "UTC_TIMESTAMP())", new MySqlParameter("@pid", pid)) > 0;
+                    "(pid, TimeAdded, TimeUpdated, IpAddress) VALUES (@pid, UTC_TIMESTAMP(), " +
+                    "UTC_TIMESTAMP(), @ip_address)", 
+                    new MySqlParameter("@pid", pid),
+                    new MySqlParameter("@ip_address", ip_address)) > 0;
             }
         }
 
@@ -1104,7 +1109,8 @@ namespace PkmnFoundations.Data
                 new MySqlParameter("@email", profile.Email),
                 new MySqlParameter("@has_notifications", profile.HasNotifications),
                 new MySqlParameter("@client_secret", profile.ClientSecret),
-                new MySqlParameter("@mail_secret", profile.MailSecret)
+                new MySqlParameter("@mail_secret", profile.MailSecret),
+                new MySqlParameter("@ip_address", profile.IpAddress)
             };
 
             if (exists)
@@ -1114,7 +1120,7 @@ namespace PkmnFoundations.Data
                     "Region = @region, OT = @ot, Name = @name, MacAddress = @mac_address, " +
                     "Email = @email, HasNotifications = @has_notifications, " +
                     "ClientSecret = @client_secret, MailSecret = @mail_secret, " +
-                    "ParseVersion = 2, TimeUpdated = UTC_TIMESTAMP() " +
+                    "IpAddress = @ip_address, ParseVersion = 2, TimeUpdated = UTC_TIMESTAMP() " +
                     "WHERE pid = @pid", _params) > 0;
             }
             else
@@ -1122,10 +1128,10 @@ namespace PkmnFoundations.Data
                 return tran.ExecuteNonQuery("INSERT INTO GtsProfiles4 " +
                     "(pid, Data, Version, Language, Country, Region, OT, Name, " +
                     "MacAddress, Email, HasNotifications, ClientSecret, MailSecret, " +
-                    "ParseVersion, TimeAdded, TimeUpdated) VALUES " +
+                    "IpAddress, ParseVersion, TimeAdded, TimeUpdated) VALUES " +
                     "(@pid, @data, @version, @language, @country, @region, @ot, " +
                     "@name, @mac_address, @email, @has_notifications, " +
-                    "@client_secret, @mail_secret, 2, UTC_TIMESTAMP(), UTC_TIMESTAMP())", _params) > 0;
+                    "@client_secret, @mail_secret, @ip_address, 2, UTC_TIMESTAMP(), UTC_TIMESTAMP())", _params) > 0;
             }
         }
         #endregion
@@ -2025,7 +2031,8 @@ namespace PkmnFoundations.Data
                 new MySqlParameter("@email", profile.Email),
                 new MySqlParameter("@has_notifications", profile.HasNotifications),
                 new MySqlParameter("@client_secret", profile.ClientSecret),
-                new MySqlParameter("@mail_secret", profile.MailSecret)
+                new MySqlParameter("@mail_secret", profile.MailSecret),
+                new MySqlParameter("@ip_address", profile.IpAddress)
             };
 
             if (exists)
@@ -2035,7 +2042,7 @@ namespace PkmnFoundations.Data
                     "Region = @region, OT = @ot, Name = @name, MacAddress = @mac_address, " +
                     "Email = @email, HasNotifications = @has_notifications, " +
                     "ClientSecret = @client_secret, MailSecret = @mail_secret, " +
-                    "ParseVersion = 2, TimeUpdated = UTC_TIMESTAMP() " +
+                    "IpAddress = @ip_address, ParseVersion = 2, TimeUpdated = UTC_TIMESTAMP() " +
                     "WHERE pid = @pid", _params) > 0;
             }
             else
@@ -2043,10 +2050,10 @@ namespace PkmnFoundations.Data
                 return tran.ExecuteNonQuery("INSERT INTO GtsProfiles5 " +
                     "(pid, Data, Version, Language, Country, Region, OT, Name, " +
                     "MacAddress, Email, HasNotifications, ClientSecret, MailSecret, " +
-                    "ParseVersion, TimeAdded, TimeUpdated) VALUES " +
+                    "IpAddress, ParseVersion, TimeAdded, TimeUpdated) VALUES " +
                     "(@pid, @data, @version, @language, @country, @region, @ot, " +
                     "@name, @mac_address, @email, @has_notifications, " +
-                    "@client_secret, @mail_secret, 2, UTC_TIMESTAMP(), UTC_TIMESTAMP())", _params) > 0;
+                    "@client_secret, @mail_secret, @ip_address, 2, UTC_TIMESTAMP(), UTC_TIMESTAMP())", _params) > 0;
             }
         }
         #endregion
diff --git a/library/Data/Database.cs b/library/Data/Database.cs
index 7bc1d64f..671f5047 100644
--- a/library/Data/Database.cs
+++ b/library/Data/Database.cs
@@ -93,7 +93,7 @@ namespace PkmnFoundations.Data
         #endregion
 
         #region Other Gamestats 4
-        public abstract bool GamestatsBumpProfile4(int pid);
+        public abstract bool GamestatsBumpProfile4(int pid, string ip_address);
         public abstract bool GamestatsSetProfile4(TrainerProfile4 profile);
         #endregion
 
diff --git a/library/Structures/TrainerProfile4.cs b/library/Structures/TrainerProfile4.cs
index 5676f58d..1c9d0c70 100644
--- a/library/Structures/TrainerProfile4.cs
+++ b/library/Structures/TrainerProfile4.cs
@@ -11,7 +11,7 @@ namespace PkmnFoundations.Structures
         {
         }
 
-        public TrainerProfile4(int pid, byte[] data) : base(pid, data)
+        public TrainerProfile4(int pid, byte[] data, string ip_address) : base(pid, data, ip_address)
         {
         }
 
@@ -25,7 +25,7 @@ namespace PkmnFoundations.Structures
 
         public TrainerProfile4 Clone()
         {
-            return new TrainerProfile4(PID, Data.ToArray());
+            return new TrainerProfile4(PID, Data.ToArray(), IpAddress);
         }
     }
 }
diff --git a/library/Structures/TrainerProfile5.cs b/library/Structures/TrainerProfile5.cs
index 3e487110..1b04a3b8 100644
--- a/library/Structures/TrainerProfile5.cs
+++ b/library/Structures/TrainerProfile5.cs
@@ -11,7 +11,7 @@ namespace PkmnFoundations.Structures
         {
         }
 
-        public TrainerProfile5(int pid, byte[] data) : base(pid, data)
+        public TrainerProfile5(int pid, byte[] data, string ip_address) : base(pid, data, ip_address)
         {
         }
 
@@ -25,7 +25,7 @@ namespace PkmnFoundations.Structures
 
         public TrainerProfile5 Clone()
         {
-            return new TrainerProfile5(PID, Data.ToArray());
+            return new TrainerProfile5(PID, Data.ToArray(), IpAddress);
         }
     }
 }
diff --git a/library/Structures/TrainerProfileBase.cs b/library/Structures/TrainerProfileBase.cs
index c199738f..636b9370 100644
--- a/library/Structures/TrainerProfileBase.cs
+++ b/library/Structures/TrainerProfileBase.cs
@@ -13,17 +13,19 @@ namespace PkmnFoundations.Structures
 
         }
 
-        protected TrainerProfileBase(int pid, byte[] data)
+        protected TrainerProfileBase(int pid, byte[] data, string ip_address)
         {
             if (data.Length != 100) throw new ArgumentException("Profile data must be 100 bytes.");
 
             PID = pid;
             Data = data;
+            IpAddress = ip_address;
         }
 
         // todo: encapsulate these so calculated fields are always correct
         public int PID;
         public byte[] Data; // 100 bytes
+        public string IpAddress;
 
         public Versions Version
         {