diff --git a/libraries/chain/market_evaluator.cpp b/libraries/chain/market_evaluator.cpp
index 27c31ae4..3cd072f2 100644
--- a/libraries/chain/market_evaluator.cpp
+++ b/libraries/chain/market_evaluator.cpp
@@ -52,6 +52,11 @@ void_result limit_order_create_evaluator::do_evaluate(const limit_order_create_o
    if( _sell_asset->options.blacklist_markets.size() )
       FC_ASSERT( _sell_asset->options.blacklist_markets.find(_receive_asset->id) == _sell_asset->options.blacklist_markets.end() );
 
+   // I. DEX Task
+   FC_ASSERT(_receive_asset->id == asset_id_type() || _sell_asset->id == asset_id_type(),
+              "No asset in the trade is CORE.");
+
+
    FC_ASSERT( is_authorized_asset( d, *_seller, *_sell_asset ) );
    FC_ASSERT( is_authorized_asset( d, *_seller, *_receive_asset ) );