By the time of ROTJ, it’s been like 3 years since Boba Fett delivered Han. (At least if we ignore supplementary material like Shadows of the Empire.) So the fact that Boba Fett is still hanging around at Jabba’s palace by the time of ROTJ would seem to indicate some kind of permanent employment with Jabba. There’s also that ridiculous scene in the Special Edition of A New Hope where we see Boba Fett as part of Jabba’s entourage. So we can infer from all this that Boba Fett fights Luke on the skiff in ROTJ because his duties include general security or protection for Jabba.
I recall that George Lucas stated somewhere that, when writing ROTJ, Boba Fett was considered basically just a random goon and nothing more. Strangely, the script for ROTJ acts like many events in ESB never happened. For example, Boba Fett doesn’t recognize Lando, and doesn’t seem to have any relationship with Vader anymore.
It’s weird because in the late 1979/early 1980 promotional material for ESB, Boba Fett was always advertised as working for Darth Vader. He was never associated with Jabba the Hutt. And in the 1978 Holiday Special (Boba Fett’s first appearance), Fett is associated with Vader, not Jabba.
But the A New Hope Special Edition scene from 1997 implies Boba Fett worked for Jabba in some capacity well before Vader hired him in ESB. And of course, ESB itself implies Boba Fett works for BOTH Vader and Jabba (and the “No disintegration!” line implies a prior relationship between Fett and Vader). But the earliest 1978/1979 promotional material emphasizes Boba Fett’s connection with Vader. Yet by the time ROTJ came out, Fett’s connection with Vader was essentially forgotten by the script.
Basically, Fett was originally marketed as Darth Vader’s minion, from 1978 thru 1980 when Empire Strikes Back was released. But then in ROTJ, Boba Fett works for Jabba in some semi-permanent capacity, and his relationship with Vader is never acknowledged.
Very interesting stuff there, I did not think about the special edition scene adding Boba Fett to Star Wars, which means that George Lucas wants him to be employed specifically by Jabba. I hate that, and don’t consider it canon, but still interesting to note.
I’ve always taken the “No disintegrations” line just to imply that Boba Fett is notorious for disintegrating his bounties, not any previous relation with Vader, even though the Holiday Special shows one of course. Correct me if I’m wrong, but I don’t think anyone actually refers to him as Boba Fett in Empire? Han goes, “Boba Fett, where!?” in Jedi(which then means he knows him, and has a history with him…) but Darth Vader I know says, “He’s all yours, bounty hunter” instead of his name.
I still find it hard to believe there’s 3 years between Empire and Jedi, did it really take that long to rescue Han? But the idea that his relationship with Jabba was strengthened between films is a plausible theory. Another being he just hasn’t been paid yet, and Jabba is making him protect him if he wants to get his payment.