Don't know how accurate this is, but it's a start:

"As its name implies, SkyGrabber is a program that grabs data being broadcast
by satellites - it acts as a radio for data feeds and lets people tune into different
data streams as they might radio stations.

Anyone downloading via a wire only shares that net link with a few neighbours.
By contrast, anyone using a satellite net connection effectively shares all the
data they are getting with everyone in the area covered by a satellite.

Those other people do not see that data because their PC is only watching for
what they want. However, SkyGrabber eavesdrops on all the data being downloaded
over a link and turns it back into whole files.

The way that data is sent over the net makes it very easy for anyone to reconstruct
files. SkyGrabber has proved popular because it has good filters that let people
sort the types of files, mp3, wmv, jpg they want to get.

It also knows about many different satellites and can be re-tuned to look at other
data streams - such as those coming from drones.

The downside is that SkyGrabber users only get what other people want."