c. You and any other involved insured must:
(1) Immediately send us copies of any demands, notices, summonses or legal papers received in connection with the claim or "suit";
(2) Authorize us to obtain records and other information;
(3) Cooperate with us in the investigation, settlement or defense of the claim or "suit"; and
(4) Assist us, upon our request, in the enforcement of any right against any person or organization which may be liable to the insured because of injury or damage to which this insurance may also apply.

d. No insureds will, except at their own cost, voluntarily make a payment, assume any obligation, or incur any expense, other than for first aid, without our consent.

**3. Legal Action Against Us.**

No person or organization has a right under this Coverage Part:
a. To join us as a party or otherwise bring us into a "suit" asking for damages from an insured; or
b. To sue us on this Coverage Part unless all of its terms have been fully complied with.

A person or organization may sue us to recover on an agreed settlement or on a final judgment against an insured obtained after an actual trial; but we will not be liable for damages that are not payable under the terms of this Coverage Part or that are in excess of the applicable limit of insurance. An agreed settlement means a settlement and release of liability signed by us, the insured and the claimant or the claimant's legal representative.

**4. Other Insurance.**

If other valid and collectible insurance is available to the insured for a loss we cover under Coverages A or B of this Coverage Part, our obligations are limited as follows:

**a. Primary Insurance**

This insurance is primary except when b. below applies. If this insurance is primary, our obligations are not affected unless any of the other insurance is also primary. Then, we will share with all that other insurance by the method described in c. below.

**b. Excess Insurance**

This insurance is excess over any of the other insurance, whether primary, excess, contingent or on any other basis:
(1) That is Fire, Extended Coverage, Builder's Risk, Installation Risk or similar coverage for your work;
(2) That is Fire insurance for premises rented to you; or
(3) If the loss arises out of the maintenance or use of aircraft, "autos" or watercraft to the extent not subject to Exclusion g. of Coverage A (Section I).

When this insurance is excess, we will have no duty under Coverage A or B to defend any claim or "suit" that any other insurer has a duty to defend. If no other insurer defends, we will undertake to do so, but we will be entitled to the insured's rights against all those other insurers.

When this insurance is excess over other insurance, we will pay only our share of the amount of the loss, if any, that exceeds the sum of:
(1) The total amount that all such other insurance would pay for the loss in the absence of this insurance; and
(2) The total of all deductibles and self-insured amounts under all that other insurance.

We will share the remaining loss, if any, with any other insurance that is not described in this Excess Insurance provision and was not bought specifically to apply in excess of the Limits of Insurance shown in the Declarations of this Coverage Part.

**c. Method of Sharing**

If all of the other insurance permits contribution by equal shares, we will follow that method also. Under this approach, each insured contributes equal amounts until it has paid its applicable limit of insurance or none of the loss remains, whichever comes first.