diff --git a/gateway/gateway.py b/gateway/gateway.py
index 0e93ea6..9a064cc 100644
--- a/gateway/gateway.py
+++ b/gateway/gateway.py
@@ -113,29 +113,25 @@ class Gateway:
         log.info(f"Published to {topic} : {payload}")
 
     def on_device_found(self, device, adv_data):
-        """BLE scan callback — filters on Thingy:52 service UUID and decodes payload."""
-        uuids = [str(u).lower() for u in adv_data.service_uuids]
-        if self.service_uuid.lower() not in uuids:
-            return
+    """BLE scan callback — filters on Adrien's preamble (0xffff) in manufacturer data."""
+    if not adv_data.manufacturer_data:
+        return
 
-        # Try manufacturer data first, then service data
-        raw = None
-        if adv_data.manufacturer_data:
-            raw = list(adv_data.manufacturer_data.values())[0]
-        elif adv_data.service_data:
-            raw = list(adv_data.service_data.values())[0]
+    raw = list(adv_data.manufacturer_data.values())[0]
 
-        if raw is None:
-            log.debug(f"{device.address} | no payload data found")
-            return
+    # Filter on preamble 0xffff (company id defined in firmware spec)
+    if len(raw) < 2 or raw[0] != 0xff or raw[1] != 0xff:
+        return
 
-        data = self.decode_payload(raw)
-        if not data:
-            log.warning(f"{device.address} | empty decoded payload")
-            return
+    log.debug(f"{device.address} | Thingy detected, raw: {list(raw)}")
 
-        log.debug(f"{device.address} | decoded: {data}")
-        self.publish(device.address, data)
+    data = self.decode_payload(raw)
+    if not data:
+        log.warning(f"{device.address} | empty decoded payload")
+        return
+
+    log.debug(f"{device.address} | decoded: {data}")
+    self.publish(device.address, data)
 
     async def run(self):
         """Start passive BLE scan and run indefinitely."""