Dex bonus while grappling

[Hypersmurf]

True but AC is not the only effect of the note it also allows sneak attack damage to apply against the pinned creature. If the pinning creature has the sneak attack ability then if the note applies to the pinner it would deal sneak attack damage with the Damage Your Opponent option as well as the Use Opponent’s Weapon option.

Does sneak attack apply to Damage Your Opponent?

-Hyp.

 

[Camarath]

Does sneak attack apply to Damage Your Opponent?

-Hyp.

I don't see anything in the sneak attack ability limiting it to attacks rather than anytime you deal damage to a target vulnerable to the sneak attack ability.

 

[Patryn of Elvenshae]

I don't see anything in the sneak attack ability limiting it to attacks rather than anytime you deal damage to a target vulnerable to the sneak attack ability.

Other, you mean, than the following?

Sneak Attack: If a rogue can catch an opponent when he is unable to defend himself effectively from her attack, she can strike a vital spot for extra damage.

The rogue’s attack deals extra damage any time her target would be denied a Dexterity bonus to AC (whether the target actually has a Dexterity bonus or not), or when the rogue flanks her target. This extra damage is 1d6 at 1st level, and it increases by 1d6 every two rogue levels thereafter. Should the rogue score a critical hit with a sneak attack, this extra damage is not multiplied.

Ranged attacks can count as sneak attacks only if the target is within 30 feet.

 

[Stalker0]

Yes. But not a weapon they're holding.

-Hyp.

Hyp, unless the quote you posted earlier is imcomplete, it doesn't say use the weapon the opponent's holding against him it says opponent's weapon. In this case, your natural weapons would apply.

 

[Hypersmurf]

Hyp, unless the quote you posted earlier is imcomplete, it doesn't say use the weapon the opponent's holding against him it says opponent's weapon. In this case, your natural weapons would apply.

Nope:

If You're Pinning an Opponent:
You can attempt to damage your opponent with an opposed grapple check, you can attempt to use your opponent’s weapon against him, or you can attempt to move the grapple (all described above).

The option to use your opponent's weapon is 'described above' - in the "If You're Grappling" section. It has this to say:

Use Opponent’s Weapon: If your opponent is holding a light weapon, you can use it to attack him. Make an opposed grapple check (in place of an attack). If you win, make an attack roll with the weapon with a –4 penalty (doing this doesn’t require another action). You don’t gain possession of the weapon by performing this action.

-Hyp.