No Radio Signals from Oumuamua

To help rule out Oumuamua as an interstellar probe, it was investigated and found to have no detectable transmissions within 1-10 GHz down to powers of at least 300 milliwatts. Yes, this could be like an uncontacted tribe on Earth in 2018 saying that the drone that surfaced in their bay wasn't sent by people because it didn't give off smoke signals - but you have to start with clear assumptions of SOME kind and test them. That such a ship-like object is passing through the solar system is exciting, but since we found it very soon after we were first capable of finding it suggests that such objects pass through our solar system all the time.