Re-equipping Equipment question.

[Borg]

Trying to find the exact ruling for this situation.

Equipment (Lightning Greaves) is equipped on creature A.
I activate lightning Greaves ( paying 0 mana ) to move it to creature B and put the ability on the stack.

My question : is Lightning Greaves still ON creature A while the ability is on the stack or not ?
I assume : yes.
Where is this covered in the rules ?

[ApothecaryGeist]

I don't have the rule #.

There is no way to unattach an equipment (except for those few that have an ability that specifically says so).  When you announce an equip ability, you choose the target creature that it will attach to (creature B).  If the ability resolves, It will move from creature A to creature B.  There will never be a time when it is not attached to one of them.  If the ability fails to resolve (say creature B was given shroud or protection from artifacts), then the equipment stays attached to creature A.

Does this answer your question?

Happy Brewing! 

[Mnemosyne]

Apothecary Geist is correct, you cannot unequip. You can only equip another creature (you control) and do so at sorcery speed not instant speed. Everything on the stack resolves between stages. If you equip another creature, the creature you moved it from is unequipped. Unless an opponent responds to the trigger, in which case it resolves before the creature loses its equipment.

502.33a Equip is an activated ability of artifact Equipment cards. The phrase "Equip [cost]" means "[cost]: Move this Equipment onto target creature you control. Play this ability only any time you could play a sorcery."

[WWolfe]

Also note, though not asked, that the activation of the equip ability can be responded to at instant speed. Meaning that the creature you are attempting to move the equipment to can be doombladed for instance in response to the equip ability.