(a) Determining benefits. This section shall apply in determining the benefits as to a person covered under the Plan for any claim determination period if, for the allowable expense incurred as to such person during such period, the sum of:

1. (1) the benefits that would be payable under this Plan in the absence of this provision, and
2. (2) the benefits that would be payable under all other Plans in the absence therein of provisions of similar purpose to this provision would exceed such Allowable Expenses.

(c) Coordination of benefits. The benefits of another Plan will be ignored for the purpose of determining the benefits under this Plan if:

1. (1) the other Plan which is involved in (b) of this section and which contains a provision coordinating its benefits with those of this Plan would, according to its rules, determine its benefits after the benefits of this plan have been determined, and
2. (2) the rules set forth in (d) of this section would require this Plan to determine its benefits before such other Plan.

(d) Order of benefit determination. For the purpose of (c) of this section, the rules establishing the order of benefit determination are:

1. (1) The benefits of a Plan which covers the person on whose expenses claim is based other than as a dependent shall be determined before the benefits of a Plan which covers such person as a dependent.

2. (2) The following guidelines apply with respect to claims regarding dependent children:

   1. (A) Except for cases of a person for whom claim is made as a dependent child whose parents are separated or divorced, the benefits of a plan which covers the person on which expenses claim is based as a dependent of a person whose date of birth, excluding year of birth, occurs earlier in a calendar year, shall be determined before the benefits of a Plan which covers such person as a dependent of a person whose date of birth, excluding year of birth, occurs later in a calendar year. If either Plan does not have the provisions of this paragraph regarding dependents, which results either in each Plan determining benefits before the other or in each Plan determining its benefits after the other, the provisions of this paragraph shall not apply, and the rule set forth in the Plan which does not have the provisions of this paragraph shall determine the order of benefits.
   2. (B) In the case of a person for whom claim is made as a dependent child whose parents are separated or divorced and the parent with custody of the child has not remarried, the benefits of a Plan which covers the child as a dependent of the parent with custody of the child will be determined before the benefits of a Plan which covers the child as a dependent of the parent without custody.
   3. (C) In the case of a person for whom claim is made as a dependent child whose parents are divorced and the parent with custody of the child has remarried, the benefits of a Plan which covers the child as a dependent of the parent with custody shall be determined before the benefits of a Plan which covers that child as a dependent of the stepparent, and the benefits of a Plan which covers that child as a dependent of the stepparent will be determined before the benefits of a Plan which covers that child as a dependent of the parents without custody.
   4. (D) In the case of a person for whom claim is made as a dependent child whose parents are separated or divorced, where there is a court decree which would otherwise establish financial responsibility for the medical, dental or other health care expenses with respect to the child, then, notwithstanding (B) and (C) of this paragraph, the benefits of a Plan which covers the child as a dependent of the parent with such financial responsibility shall be determined before the benefits of any other Plan which covers the child as a dependent child.

3. (3) When (1) and (2) of this subsection do not establish an order of benefit determination, the benefits of a Plan which has covered the person on whose expenses claim is based for the longer period time shall be determined before the benefits of a Plan which has covered such person the shorter period of time, provided that:

   1. (A) the benefits of a plan covering the person on whose expenses claim is based as a laid-off or retired employee, or dependent of such person, shall be determined after the benefits of any other Plan covering such person as an employee, other than a laid-off or retired employee, or dependent of such person; and
   2. (B) if either Plan does not have a provision regarding laid-off or retired employees, which results in each Plan determining its benefits after the other, then the provisions of (A) above shall not apply.

4. (4) When a claim under a Plan with a COB provision involves another Plan which also has a COB provision, the carriers involved should use the rules in (1) through (3) of this subsection to decide the order in which the benefits payable under the respective plans will be determined. Note:

   1. (A) In determining the length of time an individual has been covered under a given Plan, two successive Plans of a given group shall be deemed to be one continuous Plan so long as the claimant concerned was eligible for coverage within 24 hours after the prior Plan terminated. Thus, neither a change in the amount of scope of benefits provided by a Plan, a change in the carrier insuring the Plan, nor a change from one type of Plan to another, (e.g. single employer to multiple employer Plan, or vice versa, or single employer to a Taft-Hartley Welfare Plan) would constitute the start of a new Plan for purposes of this paragraph.
   2. (B) If a claimant's effective date of coverage under a given Plan is subsequent to the date the carrier first contracted to provide the Plan for the group concerned (employer, union, association, etc.), then, the absence of specific information to the contrary, the carrier shall assume, for purposes of this paragraph, that the claimant's length of time covered under that plan shall be measured from claimant's effective date of coverage. If a claimant's effective date of coverage under a given Plan is the same as the date the carrier first contracted to provide the Plan for the group coverage, then the carrier shall request the group concerned to furnish the date the claimant first became covered under the earliest of any prior Plans the group may have had. If such date is not readily available, the date the claimant first became a member of the group shall be used as the date from which to determine the length of time his coverage under that Plan has been in force.

5. (5) Some Plans have order of benefit determination rules not consistent with this section which declare that the Plan's coverage is "excess" to all others, or "always secondary". This occurs because:

   1. (A) certain Plans may not be subject to insurance section; or
   2. (B) some group contracts have not yet been conformed with this section pursuant to the effective date.

6. (6) A Plan with order of benefit determination rules which complies with this section (herein called a Complying Plan) may coordinate its benefits with a Plan which is "excess" or "always secondary" or which uses order of benefit determination rules which are inconsistent with those contained in this section (herein called a Noncomplying Plan) on the following basis:

   1. (A) If the Complying Plan is the Primary Plan, it shall pay or provide its benefits on a primary basis.
   2. (B) If the Complying Plan is the Secondary Plan, it shall, nevertheless, pay or provide its benefits first, but the amount of the benefits payable shall be determined as if the Complying Plan were the Secondary plan. In such a situation, such payment shall be the limit of the Complying Plan's liability.
   3. (C) If the Noncomplying Plan does not provide the information needed by the Complying Plan to determine its benefits within a reasonable time after it is requested to do so, the Complying Plan shall assume that the benefits of the Noncomplying Plan are identical to its own, and shall pay its benefits accordingly. However, the Complying Plan must adjust any payments it makes based on such assumption whenever information becomes available as to the actual benefits of the Noncomplying Plan.