diff --git a/freqtrade/exchange/exchange.py b/freqtrade/exchange/exchange.py
index 5273030ab..27c96a70d 100644
--- a/freqtrade/exchange/exchange.py
+++ b/freqtrade/exchange/exchange.py
@@ -92,7 +92,7 @@ class Exchange:
         # TradingMode.SPOT always supported and not required in this list
     ]
 
-    def __init__(self, config: Config, validate: bool = True,
+    def __init__(self, config: Config, *, validate: bool = True,
                  load_leverage_tiers: bool = False) -> None:
         """
         Initializes this module with the given config,