diff --git a/src/komodo_globals.h b/src/komodo_globals.h
index b4f886e4b..c46486430 100644
--- a/src/komodo_globals.h
+++ b/src/komodo_globals.h
@@ -48,7 +48,7 @@ int COINBASE_MATURITY = _COINBASE_MATURITY;//100;
 int32_t IS_KOMODO_NOTARY,USE_EXTERNAL_PUBKEY,KOMODO_CHOSEN_ONE,ASSETCHAINS_SEED,KOMODO_ON_DEMAND,KOMODO_EXTERNAL_NOTARIES,KOMODO_PASSPORT_INITDONE,KOMODO_PAX,KOMODO_EXCHANGEWALLET,KOMODO_REWIND;
 int32_t KOMODO_LASTMINED,prevKOMODO_LASTMINED,JUMBLR_PAUSE = 1;
 std::string NOTARY_PUBKEY,ASSETCHAINS_NOTARIES,ASSETCHAINS_OVERRIDE_PUBKEY,DONATION_PUBKEY;
-uint8_t NOTARY_PUBKEY33[33],ASSETCHAINS_OVERRIDE_PUBKEY33[33],ASSETCHAINS_PUBLIC;
+uint8_t NOTARY_PUBKEY33[33],ASSETCHAINS_OVERRIDE_PUBKEY33[33],ASSETCHAINS_PUBLIC,ASSETCHAINS_PRIVATE;
 
 char ASSETCHAINS_SYMBOL[KOMODO_ASSETCHAIN_MAXLEN],ASSETCHAINS_USERPASS[4096];
 uint16_t ASSETCHAINS_P2PPORT,ASSETCHAINS_RPCPORT;
diff --git a/src/komodo_utils.h b/src/komodo_utils.h
index c8c2e35b1..c6ffe4cdd 100644
--- a/src/komodo_utils.h
+++ b/src/komodo_utils.h
@@ -1541,6 +1541,7 @@ void komodo_args(char *argv0)
     }
     ASSETCHAINS_CC = GetArg("-ac_cc",0);
     ASSETCHAINS_PUBLIC = GetArg("-ac_public",0);
+    ASSETCHAINS_PRIVATE = GetArg("-ac_private",0);
     if ( (KOMODO_REWIND= GetArg("-rewind",0)) != 0 )
     {
         printf("KOMODO_REWIND %d\n",KOMODO_REWIND);
diff --git a/src/main.cpp b/src/main.cpp
index a7565e0ab..13a3121c6 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1090,6 +1090,7 @@ bool CheckTransactionWithoutProofVerification(const CTransaction& tx, CValidatio
     
     // Check for negative or overflow output values
     CAmount nValueOut = 0;
+    int32_t iscoinbase = tx.IsCoinBase();
     BOOST_FOREACH(const CTxOut& txout, tx.vout)
     {
         if (txout.nValue < 0)
@@ -1100,6 +1101,10 @@ bool CheckTransactionWithoutProofVerification(const CTransaction& tx, CValidatio
             fprintf(stderr,"%.8f > max %.8f\n",(double)txout.nValue/COIN,(double)MAX_MONEY/COIN);
             return state.DoS(100, error("CheckTransaction(): txout.nValue too high"),REJECT_INVALID, "bad-txns-vout-toolarge");
         }
+        if ( txout.nValue > 0 && ASSETCHAINS_PRIVATE != 0 && iscoinbase == 0 )
+        {
+            return state.DoS(100, error("CheckTransaction(): this is a private chain, no public allowed"),REJECT_INVALID, "bad-txns-acprivacy-chain");
+        }
         nValueOut += txout.nValue;
         if (!MoneyRange(nValueOut))
             return state.DoS(100, error("CheckTransaction(): txout total out of range"),
@@ -1742,7 +1747,7 @@ bool ReadBlockFromDisk(CBlock& block, const CBlockIndex* pindex,bool checkPOW)
 extern char ASSETCHAINS_SYMBOL[KOMODO_ASSETCHAIN_MAXLEN];
 extern uint32_t ASSETCHAINS_MAGIC;
 extern uint64_t ASSETCHAINS_STAKED,ASSETCHAINS_ENDSUBSIDY,ASSETCHAINS_REWARD,ASSETCHAINS_HALVING,ASSETCHAINS_LINEAR,ASSETCHAINS_COMMISSION,ASSETCHAINS_SUPPLY;
-extern uint8_t ASSETCHAINS_PUBLIC;
+extern uint8_t ASSETCHAINS_PUBLIC,ASSETCHAINS_PRIVATE;
 
 CAmount GetBlockSubsidy(int nHeight, const Consensus::Params& consensusParams)
 {