diff --git a/plugins/eddn.py b/plugins/eddn.py
index 29de4910..6533f638 100644
--- a/plugins/eddn.py
+++ b/plugins/eddn.py
@@ -789,8 +789,18 @@ MAP_STR_ANY = Mapping[str, Any]
 
 
 def is_horizons(economies: MAP_STR_ANY, modules: MAP_STR_ANY, ships: MAP_STR_ANY) -> bool:
-    return (
-        any(economy['name'] == 'Colony' for economy in economies.values()) or
-        any(module.get('sku') == HORIZ_SKU for module in modules.values()) or
-        any(ship.get('sku') == HORIZ_SKU for ship in (ships['shipyard_list'] or {}).values())
-    )
+    economies_colony = False
+    modules_horizons = False
+    ship_horizons = False
+
+    if isinstance(dict, economies):
+        economies_colony = any(economy['name'] == 'Colony' for economy in economies.values())
+
+    if isinstance(dict, modules):
+        modules_horizons = any(module.get('sku') == HORIZ_SKU for module in modules.values())
+
+    if isinstance(dict, ships):
+        if ships.get('shipyard_list') is not None:
+            ship_horizons = any(ship.get('sku') == HORIZ_SKU for ship in ships['shipyard_list'].values())
+
+    return economies_colony or modules_horizons or ship_horizons