Between 1962 and 2010 there were over 120 known witnesses to various types of events that corroborate, verify, enforce and prove the authenticity of Billy Meier's experiences.
The types of events are as follows:
- Clean-shaven Meier departs & returns a day later with a many-day growth of beard, after a (5-day space-trip) contact.
- Had a daytime sighting of a beamship or related craft.
- Caught sight of one of the ETs, such as Quetzal, Ptaah or Asket.
- Saw the fir tree that Semjase posed her ship on all sides of after it was damaged, glowed in the dusk and later disappeared.
- Saw and/or photographed a crop-circle like pattern in the grass or in ice soon after a contact.
- Heard the sound of a beamship, or its loud noise made during a tape-recording session, or a related UFO sound.
- Heard the voice of a Plejaren or Plejaren associate speaking to Meier.
- Witnessed Billy receiving or sending a telepathic message, as confirmed by an immediately following event.
- Had a night-time UFO sighting associated with one of Billy's contacts or with a night "UFO demonstration".
- Had a night-time beamship sighting while Meier was aboard the craft and in radio communication with the witness.
- Passed PSE (Psychological stress evaluation) test.
- Viewed Billy's dozen or so photos of how San Francisco would look after a future devastating earthquake.
- Took photo(s) of the craft/beamship.
- Saw Billy suddenly return or appear after a contact.
- Viewed the disappearing tree demonstration.
- Noticed Billy suddenly vanish (just before a contact).
- Witnessed Billy rapidly typing out a Contact Report the day or so after, at a speed much faster than is normal for him.