Between November 2005 and April 2011 information was leaked onto the Internet, claiming that the US Government made contact with its inhabitants after a crashed UFO with a surviving crew member was found. In 1965 twelve volunteers were exchanged as ambassadors. (A first attempt in 1964 had failed). They stayed on Serpo for thirteen years before eight of them returned to Earth. (Two died, and two preferred to remain). The inhabitants of Serpo are referred to as the Eben. It is not clear, however, whether this would be their name, or whether the expression is used in a generic way to refer to Extraterrestrial Biological ENtities.

An anonymous source claiming to work for British intelligence services claimed in 2077 that the real name of the planet was Seinu, and not Serpo.

The name Serpo is also used for the covert project with regard to the exchange of these ambassadors. One source claims the real name of the project was Crystal Knight. As such it belongs to the Aquarius range of covert projects and is also related to the projects Plato and Sigma. (Allegedly, the name of the exchange project was changed to Serpo when the ‘ambassadors’ returned in 1978).