These are the people I know who are working for him

Linderman
Parkman's dad
Knox
Flint
daphne - still undecided
hiro - still undecided

who else?

Arthur's doctor
The rest of the nameless employees who work at Pinehearst

Linderman's dead. Has been since S1. What you've been seeing, as they made crystal clear a couple episodes ago, is a hallucination caused by Maury.
Daphne is definitely working for him- although for how much longer is unclear.
Hiro is also working for him- but probably only until he thinks he can take him down.

Great topic. We can keep track of the roster here.

Hiro is probably in so he can find the holder of the formula halves, and we saw him in the future doing things against Pinehearst, so he probably won't be in there for long.

I think Hiro is really working for himself, ecspecially after african Isaac is done with him.

Hiro's working for Angela Petrelli.

Yeah he doesn't have too many employees, but I think the real question is why is Maury or anyone like the doctor helping him so much? Why do you help a guy who can take your ability from you when you can easily dispatch with him while he is so reliant on all the medical equipment? What are they afraid of? Doesn't make sense to me. Maury obviously is not his "friend" and is afraid of him.

Because they believe in Pinehearst's/Arthur's cause?

do we want to count those working in the future?

Claire and Haitian would go with that group as well

Don't forget Future Ando.

I forget, Citizen... How do you know where Future Ando's loyalties will be?

Hiro is doing it for the Legacy his father left him.

Angela, Adam, and the African guy are like those persons in RPG you get clues for your quest.

Now he knows the faces of his enemies but he'll have to discover who his real nemesis is.

For him to save the world.

Knox, Flint, Daphne have literally no idea what his cause is. The only one who does is Maury, and Maury is scared of Arthur, so again, I wouldn't be helping the guy who can easily take my ability, that's for sure. There must be something he has on Maury.

I think we don't know if Knox doesn't know the cause - he seemed pretty in the loop. We don't know if Flint knew Arthur before he was in jail.

One thing that I suspect is that Flint is the brother of Meredith and thus Claire's uncle. So basically he's working for his sister's baby's daddy's daddy

I wouldn't be surprised to find out Knox was Charles Deveaux's ****** son or DL's half-brother.

I think most of these people are picked because they are connected to the company founders or their extended family.

I also believe Daphne is Linderman's daughter. His name is Daniel. Daphne's grandmother and alternate future daughter were both named Daniella.

Just one thing. Linderman's folks disowned him for being a Mutie (Mutant).

Citizen,

Arthur controls by fear.

Creator

I'd like to know where Arthur has been all year (April 2006 - April 2007 in Heroes time). Who really tried to kill him? If it really was a suicide attempt, who saved him, and has he been bedridden the whole time? Why did he leave Primatech and when/how did he take over Pinehearst? An upcoming two-parter is titled "The Eclipse" - hopefully that is a flashback episode that will answer all these questions.