3. Other than as described in B.2. above, we will not be obligated to investigate, settle or defend any claim or suit against you. However, we will have the right at our discretion, but not the duty, to participate in the investigation, settlement or defense of any claim or suit that, in our opinion, may involve insurance under this Coverage Form.

4. We will pay with respect to any claim or suit we defend:

a. All expenses we incur;

b. All court costs taxed against an insured on amounts payable by this insurance;

c. Pre-judgment interest awarded against an insured on that part of the judgment we pay. If we make an offer to pay the applicable Limit of Insurance, we will not pay any pre-judgment interest based on that period of time after the offer

d. All interest on the amount of any judgment we pay that occurs after entry of the judgment and before we have paid, offered to pay, or deposited in court the part of the judgment that is within our applicable Limit of Insurance.

5. Costs of Defense and Supplementary Payments will not reduce the Limits of Insurance of this Coverage Form unless the limits of insurance provided by "controlling underlying insurance" are reduced by such defense and expense payments, in which case these payments are included within and will reduce the Limits of Insurance of this Coverage Form.

6. If defense is transferred to us due to the limits of "underlying insurance" being exhausted due to the payment of claims or if we transfer defense to another insurer specifically written as excess over this Coverage Form or to an insured or their designated representative, we will cooperate in the transfer of control of defense.

7. All obligations for Defense and Supplementary Payments end when we have used up our applicable limits of insurance.

C. Exclusions

Unless otherwise stated in the Declarations, this insurance does not apply to, nor shall we have a duty to defend, any claim or suit arising out of or resulting from:

1. Anything excluded by the "underlying insurance"; or

2. Any coverage that is provided in any "underlying insurance" with a limit that is included within and lower than "underlying limits of insurance", commonly referred to as a sub-limit.