I don't see why not. Though if you want that specific one you'll need to know it's name or something like that. Also you'll have an angry caster on your hands to deal with. Good luck.
You can call an outsider, but can't make it serve as your familiar without the feat. Making an outsider do what you say, and having it join with you on the level of a familiar are two different things.
You can call an outsider, but can't make it serve as your familiar without the feat. Making an outsider do what you say, and having it join with you on the level of a familiar are two different things.
I think you're making the same mistake I did when I first read OP's question, but he's not asking if you can use PB to gain a familiar:
Witch A has an Imp familiar. We'll call him Squiggles.
Wizard B uses a Planar Binding spell and specifically calls Squiggles to be trapped in the spell.
Question being, is this possible?
He has to know the familiar's true name to get that specific outsider instead of another outsider that is the same type of creature, but other than that I don't see why it would not work.
If you just call for an imp then you get a random imp. Maybe I am incorrect about the True Name, but you calling a specific outsider required specific information in 3.5. PF has not touched on what that is yet. Most GM's would at least require the creature's given name. Being that familiars don't have the effect they did on casters in 3.5, the wizard might just make another familiar. Bad RP maybe, but rules legal. Of course if the caster is evil then it would be understandable.
I am going to rule no (with a caveat).
Planar binding is a calling spell. Calling spells specifically transport a creature from another plane to yours.
"Calling: a calling spell transports a creature from another plane to the plane you are on. The spell grants the creature the one-time ability to return to its plane of origin, although the spell may limit the circumstances under which this is possible. Creatures who are called actually die when they are killed; they do not disappear and reform, as do those brought by a summoning spell (see below). The duration of a calling spell is instantaneous, which means that the called creature can't be dispelled."
As such you probably would not be able to call the Imp to you as it is more than likely serving the wizard on the same plane as you. However, if the wizard was on a different plane than you AND you knew the imp's name, then I would say that it would work.
Lab_Rat beat me to it. :(
If you just call for an imp then you get a random imp. Maybe I am incorrect about the True Name, but you calling a specific outsider required specific information in 3.5. PF has not touched on what that is yet. Most GM's would at least require the creature's given name. Being that familiars don't have the effect they did on casters in 3.5, the wizard might just make another familiar. Bad RP maybe, but rules legal. Of course if the caster is evil then it would be understandable.Ultimate Magic has the rules for True Names, which re not required to use Planar Binding on a specific outsider, a given/common name is sufficient. Having the True Name generally gives more power over the creature.
Against a Wizard, kidnapping the familiar is mainly used to get intelligence to help you fight said Wizard. Used against a Witch, all of that is possible, but you also have the Witch's equivalent of the spellbook in your grasp.
PF has no rules on such things making it a GM fiat area. 3.5 you would at least have to specify Bob the Balor as an example.
If you use the spell and try to say "That imp that you know I want. No I don't know his name, but I still want to call him." most GM's I know will send you a random imp.