Would Voldemort brand the Imperiused Death Eaters (like Stan Shunpike) with the Dark Mark?
Stan Shunpike was never a Death Eater - the people Voldy Imperiused were just tools, not actual DEs. So Shunpike was never an actual DE, he was just acting on orders through the curse.
And since Voldy Imperiused people just to do his dirty work, they were never actual DEs, even if they were convicted of DE activity. So no, he wouldn't have branded them.
There isn't a specific answer in any of the books, but it wouldn't really make sense for him to brand any of the Imperiused Death Eaters.
The idea behind the Imperius Curse is that it is not obvious to the people around the Imperiused person. If someone were Imperiused, they could pass information about the Order or the Ministry back to Voldemort; their colleagues would continue business as usual. However, if the person was branded with the Dark Mark, it might be seen and recognized by people in the Ministry or Order.
Also, in the case of Fenrir Greyback, he was helping Voldemort without being Imperiused, and yet he was not branded with the Dark Mark. This suggests that people such as him are not important enough to be branded.
So, coincidentally, this means that only his inner circle would have gotten branded with the Dark Mark? This raises another question.
Why did Voldemort not brand himself with the Dark Mark?
This is a much harder question to answer. I will, however, take a guess.
A brand always seems to signify that the people with it are under command of the one without it. Ranchers, for example, brand their horses and cattle, but wouldn't brand themselves. This would say "I'm better than all of them, so I'm their leader." This also makes sense because while the Death Eaters must come to Voldemort when the Dark Mark is touched, Voldemort cannot be ordered around like that.
Besides, Voldemort doesn't need a Dark Mark to be recognized as the great Dark wizard...
Well firstly, I believe it was painful when Voldemort pressed the Mark. I believe it is canon that it was painful for Wormtail when he recalled the Death Eaters. Voldemort also thinks that his followers are completely faithful, and would follow him anywhere. I don't think it occured to him that he would ever need to have a method to call the Death Eaters to him when he is by himself. Also like Ravenclaw Soprano said, he was their leader, and he liked having a distinction between himself and everyone else. Also, within the hierachy of the Death Eaters, it would be proof of being in his center circle, which would be an incentive of sorts for the lower ones.
Originally Posted by Ryan The Wizard
Hope that helped!
I know there are no references in the books to Voldemort branding himself, but I don't think he had to. The Marks are a way of summoning them to him. All he has to do is touch the Mark on one of them and the others have to come.
As for in DH when they touched the Marks to let him know they had Harry, I think that is because he is connected to the Marks. Since he 'designed' them and actually branded them he would know when they were being used. Almost like a telepathic link to them, if that makes sense.
The Marks were not given to any but the most valued of his followers. Snape himself mentioned the Marks as a way of recognizing each other. Only the dozen odd DE's in GoF and the few more in The Dark Lord Ascending would have the Mark.
Hope that helps,
I agree with red haired mom. Voldemort as the leader would be the only one to summon his DEs, meaning whatever the reason was that it would be important. In GOF the DEs were frightened that the mark was burning, which ment Voldemort was back and with a DE (Wormtail) Also Voldemort wouldn't brand non-purebloods like Greyback (DH) so, I'm not positive Stan was a pureblood or just a person Harry knew, which means Harry would be confused to kill Stan or leave him be (Voldemort might have known Harry knew Stan). hope that helped!