The Blue Sun Corporation is a large, diversified corporation (or possibly Megacorporation), compared by creator Joss Whedon to a combination of Walmart and Microsoft. The company is broadly hinted as being less benign than either of those two companies, and plays a role more comparable to that played by Weyland-Yutani in the Alien franchise or Omni Consumer Products in the RoboCop franchise.

It is worth mentioning that in the few instances when River Tam exhibits bizarre or violent behaviour, Blue Sun is involved. In the episode "Shindig", River rips the labels off cans bearing the Blue Sun logo, and in "Ariel", Jayne Cobb is wearing a Blue Sun shirt when River slashes him. The writer of this episode confirms in the director's commentary on the DVD set, that River was, in fact, attacking the "Blue Sun" logo on Jayne's shirt and not Jayne himself. Thus her comment, "He looks better in red," probably means that she prefers it to the blue of the logo.