Subrogation, Contribution, and Partial Insurance under the British Marine Insurance Act

Subrogation, Contribution, and Underinsurance under the Marine Insurance Act 1906

Subrogation, contribution, and underinsurance under the Marine Insurance Act 1906 refer to the system that organizes rights acquired by the insurer after paying an insurance claim, the adjustment of burden among multiple insurers covering the same loss, and the insured’s self-bearing portion when the sum insured is insufficient relative to the insurable value.

Section 79 of the Marine Insurance Act 1906 defines the Right of Subrogation, Section 80 defines the Right of Contribution, and Section 81 defines the Effect of Underinsurance.

In marine cargo insurance, after the insurer pays indemnity for a cargo incident, they may claim against a carrier, NVOCC, freight forwarder, warehouse operator, terminal, stevedore, or truck carrier, among others.

Furthermore, if overlapping insurance policies exist on the same cargo, such as a seller’s insurance and a buyer’s open cover, it may be necessary to adjust the final burden ratio among multiple insurers.

When the sum insured is less than the insurable value, not only may the portion exceeding the sum insured be unrecoverable in total loss cases, but the insured may also bear the uninsured proportion in partial loss cases.

In this article, the term “subrogation” is generally used to indicate the legal system, and “right of subrogation” is used when the insurer specifically claims against a third party.

Scope Covered in This Article

Item	Scope Covered in This Article	Scope Covered in Other Articles
Section 79	Subrogation by insurers in total loss and partial loss, rights regarding salvage and third parties	Overview of Subrogation under the entire Marine Insurance Act 1906
Subrogation in Total Loss	Rights to inherit the insured’s residual interests on items for which total loss insurance claims have been paid	Details of Actual Total Loss, Constructive Total Loss, and Notice of Abandonment
Subrogation in Partial Loss	Structure of subrogation to rights and remedies within the scope of paid insurance claims without acquisition of ownership of the insured object	Calculation of repair costs, depreciation, residual value, and partial loss amounts
Section 80	Contribution among insurers in case of double insurance	Contract structures of umbrella policies, individual policies, and co-insurance
Section 81	Treatment of underinsurance and uninsured portions as self-insurance	Specific methods of determining invoice value, sum insured, insurable value, and claim amounts
Protection of Rights	Accident notifications, Claim Letters, notification deadlines on B/L, limitation periods, and evidence preservation	Details of carrier liability, NVOCC liability, and cargo claim procedures
General Average and Salvage Charges	Possibility of insured’s contribution caused by underinsurance	General Average Guarantee, General Average Bond, calculation of salvage charges, and contributions
Sections Following Section 82	Clauses outside the scope of this article and their reasons	Premium return, mutual insurance, supplementary provisions, interpretive provisions, and schedules

The existing article titled “Marine Insurance Act 1906” provides a cross-sectional explanation of major concepts such as insurable interest, Fair Presentation of the Risk, Warranty, Constructive Total Loss, General Average, and subrogation.

This article limits its scope to Sections 79 to 81 and provides detailed explanations of subrogation after indemnity payment, contribution among insurers under double insurance, and underinsurance on a clause-by-clause basis.

Purpose and Background of the System

Marine insurance is a system designed to indemnify the insured for losses incurred due to insured events, within the limits defined by the insurance contract. It is not intended to provide the insured with a gain exceeding the amount of the loss caused by the incident.

If the insured receives full indemnity for the loss from the insurer and then recovers the entire amount for the same loss from the carrier or other liable party, this results in double recovery exceeding the actual damage.

Subrogation under Section 79 is a system that allows the insurer, after paying the insured’s claim, to exercise the rights or remedies that the insured held against third parties.

When multiple insurance contracts overlap on the same insured interest, if only one insurer bears the final loss, unfairness arises among insurers. Section 80 provides a framework for apportioning liability among insurers according to the amount for which each insurer is contractually responsible.

Conversely, where the sum insured is less than the insurable value, the insurer has not assumed the uninsured portion. Section 81 establishes a structure treating the insured as self-insuring the uninsured part.

Overview of Sections 79–81

Section	System	Basic Content	Main Parties	Situations Relevant to Marine Cargo Insurance
Section 79	Subrogation	After paying insurance claims, the insurer subrogates to the rights and remedies held by the insured	Insured, insurer, liable third parties	Subrogated recovery claims against carriers, NVOCCs, warehouse operators, and stevedores
Section 80	Contribution	When overlapping insurance results in over-insurance, each insurer proportionally shares the loss	Insured, multiple insurers	Overlapping coverage between seller’s insurance and buyer’s insurance, or between blanket policies and individual policies
Section 81	Underinsurance	When the sum insured is less than the insurable value or the declared value on the policy, the insured bears the uninsured portion	Insured, insurer	Under-declaration of insurable value, omission of freight addition, currency errors, and exceeding policy limits

Comparison of Subrogation, Contribution, and Underinsurance

Comparison Item	Subrogation	Contribution	Underinsurance	Key Points in Practice
English Term	Subrogation	Contribution	Underinsurance	These three are distinct systems and should not be confused
Main Purpose	Recovery from responsible third parties and prevention of double recovery	Fair allocation of burden among multiple insurers	Clarification of the insured’s responsibility for uninsured portions	Clarify which parties bear responsibility at the outset
Trigger Timing	After the insurer has paid indemnity to the insured	When multiple insurance contracts cover the same loss	When the sum insured is insufficient compared to the insurable value	Verification is important both at attachment of insurance and after loss
Main Counterparties	Carrier, NVOCC, warehouse operator, etc.	Other insurers	The insured party themselves	Distinguish between subrogation claims and inter-insurer contribution
Impact on the Insured	Need to preserve rights against third parties	Obligation to declare other insurance contracts to the insurer	May need to bear uninsured portion personally	Concealing information can affect claim payment and recovery
Main Documents for Confirmation	B/L, Claim Letter, Survey Report, receipts, and loss documentation	All insurance policies, insurable interest, sum insureds, and insurance periods	Invoices, insurable value, sum insured, freight charges, and exchange rates	Check documents both at contract formation and after loss

Section 79　Right of Subrogation

Section 79 stipulates the right of subrogation that arises when the insurer pays a total loss or partial loss claim.

Subrogation is the legal mechanism by which, after indemnifying the insured for a loss, the insurer acquires the right to exercise the rights or remedies that the insured had against a third party responsible for the loss or liable under the policy.

The insurer does not obtain any stronger rights than those originally held by the insured by making the insurance payment.

If the insured’s claim against the carrier is subject to limitations of liability, exclusions, notice deadlines, or statutes of limitation, the insurer’s right of subrogation is generally subject to the same restrictions.

If the insured does not have a valid claim against the carrier, the insurer’s payment of the insurance proceeds does not create a new claim right.

Subrogation in Case of Total Loss

Section 79(1) states that when the insurer has paid out the indemnity for a total loss covering the whole or a proportionate part of the insured subject matter, the insurer acquires the right to step into the insured's position regarding any residual interest related to the indemnity paid.

Even in cases where cargo is processed as a total loss, damaged machinery, parts, raw materials, packaging materials, or salable remnants may remain.

The insurer, having paid for a total loss, may exercise rights over any residual interest in the subject matter, including recovering proceeds from the sale of remnants or claims against third parties.

However, Section 79 does not imply that the insurer automatically takes physical possession of the remnants at the moment the indemnity is paid.

Ownership, possession, storage, inspection, sale, or disposal of remnants must be confirmed by referring to the insurance settlement statement, policy terms, residual value, storage and disposal costs, and agreements with the insurer.

Subrogation in Case of Partial Loss

Section 79(2) explicitly states that when the insurer pays insurance money for a partial loss, the insurer does not acquire ownership of the insured property or the remaining portion.

On the other hand, the insurer is subrogated to the rights and remedies held by the insured at the time of the incident, to the extent of the indemnity paid.

For example, if part of the cargo is damaged and the insurer pays for repair costs or the decrease in value, the cargo itself generally remains the property of the insured.

The insurer may pursue subrogation claims against the carrier, warehouse operator, terminal, or stevedore responsible for the damage, based on the insured’s original claims.

Therefore, the understanding that "an insurer who pays insurance always acquires ownership of the damaged cargo" is incorrect.

Trigger Point of Subrogation and Preservation of Rights

Subrogation under Section 79 generally arises when the insurer pays the insured the insurance proceeds.

However, the legal subrogation is not necessarily complete solely by the insurer’s approval of the payment, acknowledgment of payment liability, or confirmation of the sum insured.

Nonetheless, the rights exercised by the insurer after payment are based on the rights and remedial measures the insured had from the time of the loss.

Therefore, the insured must notify the carrier of the loss, submit Claim Letters, record damage on receipts, take photographs, conduct surveys, and manage the contractual or statutory time bar immediately after the loss occurs, without waiting for the insurance payment.

If nothing is done until the insurer pays, and the right of claim against third parties is lost due to the time bar or expiration of the time bar, the insurer’s subsequent subrogation may find no valid claim rights remaining.

Subrogation and Prevention of Double Recovery

One of the principal purposes of Subrogation is to prevent the insured from recovering the same loss twice from both the insurer and a responsible third party.

If the insured receives settlement proceeds or damages from a carrier or another third party after the insurance claim has been paid, the recovery should be reported to the insurer.

Not every amount recovered from a third party automatically belongs to the insurer. As a general rule, the insurer is entitled only to the part of the recovery that reduces the layer of loss indemnified by that insurer. Where the insured retains loss above the policy limit, a deductible, an uninsured proportion or another uninsured loss, the priority between those amounts and the insurer’s subrogated interest must be determined.

In the absence of contrary policy wording, English case law generally applies a “top-down” allocation. Third-party recoveries are first applied to uninsured loss above the highest insured layer, then to insured layers from the highest layer downwards, and only afterwards to a deductible or retention situated below the insured layers.

It is therefore inaccurate to state as a universal rule that every uncompensated loss of the insured always ranks ahead of the insurer. The result may differ depending on whether the uninsured loss lies above the insurance cover or constitutes a lower deductible or retention, and on whether the policy contains an express recoveries clause.

If the insured independently settles with the carrier and signs a full release or waiver of rights, the insurer’s subrogated recovery rights may be prejudiced.

Position in Case Law

The Marine Insurance Act 1906 codifies the basic structure of Subrogation in marine insurance. Its practical application, the allocation of third-party recoveries and the protection of the insurer’s rights are also shaped by English case law.

Castellain v Preston is a leading authority for the principle that indemnity insurance compensates loss and should not place the insured in a better financial position than if the insured event had not occurred.

Lord Napier and Ettrick v Hunter considered how third-party recoveries should be allocated where insurance covers different layers of loss and the insured retains uninsured layers. In the absence of contrary contractual wording, the case supports a “top-down” approach to allocation.

Under that approach, recoveries first reduce uninsured loss above the highest limit of insurance. They are then applied to the insured layers from the highest layer downwards. A deductible or retention below the insured layers is recovered only after those insured layers have been reached. The insurer benefits only from the part of the recovery that reduces the layer of loss it indemnified; it does not take amounts referable to a separate uninsured layer outside its indemnity.

The top-down approach has subsequently been reaffirmed in English authority. It is not, however, an inflexible rule for every policy structure. Express recovery-allocation clauses, proportional participation by the insured in the same layer, or a materially different loss structure may produce a different result.

Accordingly, the allocation analysis should identify the total loss, policy limits, the particular layer paid by each insurer, uninsured loss above the cover, deductibles or retentions below the cover, and any express recovery provisions in the policy.

Differences between Subrogation, Residual Interest, and Assignment of Rights

System	Basic Meaning	Legal Basis	Subject	Practical Considerations
Subrogation	After payment of insurance money, the insurer exercises the rights and remedies of the insured	Law and insurance contract	Claims for damages against third parties, etc.	The insurer does not acquire rights beyond those held by the insured
Acquisition of Residual Interest in Total Loss	The insurer inherits the insured’s remaining interests in the subject paid as total loss	Section 79(1)	Salvage, sale value, etc.	Method of storage, sale, or disposal should be confirmed with the insurer
Assignment of Rights	Transfer of claims and rights by agreement between the parties	Assignment contract	Rights transferable by contract or law	Legal basis differs from subrogation
Mandate	The insurer or others carry out claim procedures in the name of the insured	Power of attorney or contract	Claims, negotiations, litigation procedures, etc.	Distinguish between the name under which the claim is made and ownership of recovered proceeds

Counterparty Requiring Preservation of Rights in Subrogation Claims

Counterparty	Expected Liability	Main Contracts/Documents	Key Points for Preserving Rights
Marine Carrier	Loss, damage, or shortage during maritime transport	Master B/L, receipt, shipping records	Check notification deadlines and limitation periods under the B/L terms
NVOCC	Contracting Carrier liability under House B/L	House B/L, carriage terms, transport arrangement records	Distinguish liability relationship from Master B/L carrier
Freight Forwarder	Arrangement errors, instruction violations, communication errors, etc.	Quotation, booking, emails, service terms	Confirm whether acting as Simple Intermediary or contractual party
Warehouse Operator	Damage, wetting, theft, poor temperature control during storage	Warehouse receipt, storage terms, stock-in/out records	Identify accident period and storage liability
Terminal/Stevedoring Operator	Dropping, collision, mishandling during cargo handling	EIR, work records, photos, CCTV footage	Confirm responsible party and timing of accident
Truck Carrier	Traffic accidents, cargo collapse, or theft during inland delivery	Waybill, dispatch records, receipt	Check inland carriage terms and notification deadlines

Section 80: Right of Contribution

Section 80 governs contribution between insurers where the insured is over-insured by double insurance within Section 32.

The existence of double insurance and the scope of contribution for a particular casualty should be analysed in two stages.

At the first stage, Section 32 requires two or more policies effected by or on behalf of the same insured on the same marine adventure and the same insurable interest, or part of it, with aggregate sums insured exceeding the indemnity permitted by law. These are the matters relevant to the existence of over-insurance by double insurance.

At the second stage, the parties determine whether each policy is actually liable for the loss that occurred. Covered perils, the policy period, the insured transit, exclusions, deductibles, limits and specific conditions are not separate statutory ingredients of double insurance. They define the extent to which the insurers share liability for the particular casualty and therefore the amount subject to contribution.

If one insurer pays more than its proper share of a loss for which another insurer is also liable, the paying insurer may seek contribution from the other insurer.

Contribution is distinct from a subrogated recovery against a carrier or another responsible third party. Subrogation concerns the relationship between the insurer and the responsible third party. Contribution concerns insurers that are liable for the same loss.

Requirements for Double Insurance and Scope of Contribution

Legal Stage	Confirmation Item	What Must Be Confirmed	Typical Example	Where It Does Not Match
Existence of Double Insurance	Same Marine Adventure	Whether the policies cover the same cargo and transit, or the same relevant part of that adventure	The same invoice cargo on the same shipment	Separate shipments or distinct cargo lots may not constitute the same marine adventure
Existence of Double Insurance	Same Insurable Interest	Whether the policies protect the same economic interest of the same insured, or part of it	The same buyer’s interest in loss of or damage to the same cargo	The seller and buyer may hold different interests even in the same physical goods
Existence of Over-insurance	Aggregate Sums Insured	Whether the combined sums insured exceed the indemnity that the insured may lawfully recover	Both policies insure the full amount of the same cargo interest	If the aggregate cover does not exceed the permissible indemnity, Section 80 contribution may not arise
Scope of Contribution	Actual Covered Peril	Whether the casualty that occurred is covered under both policies	Both policies cover the same accidental wet damage	If one policy covers only war risks, it is not liable for an ordinary wet-damage casualty
Scope of Contribution	Policy Period and Insured Transit	Whether the casualty occurred while both policies were in force and within both insured transits	Both policies cover the location and time of the casualty	Different attachment or termination points may leave only one insurer liable
Calculation of Contribution	Exclusions, Deductibles, Limits and Conditions	The amount for which each insurer is contractually liable for the actual loss	Neither policy excludes the casualty and each insurer’s liability is established	Only the amount for which an insurer is liable enters the contribution calculation

Situations of Overlapping Coverage in Marine Cargo Insurance

In marine cargo insurance, overlaps may occur when both the seller and the buyer arrange insurance independently.

For example, under CIF terms, the seller may arrange insurance, while at the same time the buyer’s open cover automatically covers all imported cargo.

There are also cases where a trading company reports the cargo to its open cover, while the actual cargo owner separately arranges individual insurance, or where group companies file separate declarations for the same cargo.

However, the mere existence of multiple insurance policies does not automatically constitute overlapping insurance under Section 80.

The first step is to determine whether the policies concern the same marine adventure and the same insurable interest, and whether their aggregate sums insured exceed the permissible indemnity. The second step is to determine whether the actual casualty falls within both policies by comparing the covered peril, policy period, insured transit, exclusions, deductibles and limits.

Basic Concept of the Contribution Ratio

Under Section 80, each insurer shares the loss proportionally according to the amount of liability under their respective contracts.

For example, assume Insurer A is liable for up to 6 million yen and Insurer B for up to 4 million yen for the same loss, with the compensable damage amounting to 5 million yen.

If the contractual liability ratio is 6 to 4, the approximate final burden would be 3 million yen for Insurer A and 2 million yen for Insurer B.

If Insurer A initially pays the insured the full 5 million yen, Insurer A may seek a 2 million yen contribution from Insurer B.

However, in actual calculations, it is necessary to verify each contract’s deductible, limit, covered risks, insurable value, other insurance clauses, and scope of contractual liability.

Section 81　Effect of Underinsurance

Section 81 provides that when the insured has coverage for an amount less than the insurable value, or when the sum insured on a valued policy is less than the stated valuation, the uninsured portion will be considered self-insured by the insured.

Underinsurance refers to a situation where the full value of the insured property is not covered, and only a portion is set as the sum insured.

The uninsured portion of the risk is borne by the insured rather than the insurer.

Therefore, the effect of underinsurance is not limited to the sum insured being the maximum payout in the event of total loss.

Under the Marine Insurance Act 1906’s indemnity structure, even in cases of partial loss, the insured may bear a portion of the loss proportional to the ratio of the sum insured to the insurable value.

However, the actual insurance payout will vary depending on whether the policy is valued or unvalued, the insurance policy terms, applicable clauses, deductibles, limits, and any specific endorsements.

Numerical Examples of Underinsurance

Example	Insured Value	Sum Insured	Loss	Basic Concept
Total Loss	¥10,000,000	¥7,000,000	Total loss of the cargo	The insurer's liability is basically limited to ¥7,000,000, leaving ¥3,000,000 uninsured
Partial Loss	¥10,000,000	¥7,000,000	¥2,000,000 loss	If the insured proportion is 70%, under the MIA basic framework, the insurer bears ¥1,400,000 and the insured bears ¥600,000
Underinsurance and Deductible	¥10,000,000	¥7,000,000	¥2,000,000 loss with deductible	The insured proportion calculation and the application of the deductible should be confirmed in the policy document
Valued Policy	Policy declared value ¥12,000,000	¥9,000,000	¥3,000,000 loss	Uninsured portion is confirmed based on the insured proportion relative to the policy declared value

The above examples illustrate the basic framework under the Marine Insurance Act 1906.

Actual payment amounts vary depending on the insurance policy, applicable clauses, whether the policy is valued or unvalued, deductibles, limits of liability, and individual terms.

Main Causes of Underinsurance

Cause	Specific Details	Reference Documents	Prevention Methods
Under-declaration of Invoice Amount	Failure to declare some items, additional charges, or price changes	Commercial Invoice, Sales Contract, Additional Invoice	Reconcile the final total invoice amount with the insurance notification
Omission of Freight, Insurance Premium, etc.	Failure to add costs that should be included in the insurable value	Freight Details, Quotation, Insurance Terms	Confirm the insurance attachment criteria and add-on rates in the contract
Currency Conversion Errors	Use of incorrect currency or outdated exchange rates	Invoice, Exchange Records, Insurance Notification	Use the conversion method specified in the insurance contract
Failure to Declare Multiple Invoices	Multiple invoices exist for a single shipment	Invoice List, Packing List, Bill of Lading	Verify not only the B/L but all invoices
Incorrect Registration of Partial Shipments	Only part of the lot declared; remaining goods not insured	Booking, Bill of Lading, Shipment Details	Reconcile quantities and declared amounts per shipment
Errors in Notification for Open Cover	Incorrect notification amount, insured transit, or cargo details	Insurance Declaration Data, Invoice, Monthly Statement	Match insurance declarations with accounting and shipment data
Increase in Cargo Value	Price, processing costs, or additional charges increased after contract	Amended Contract, Additional Charges, Processing Records	Notify increases before the start of transit
Exceeding Insurance Limit	Insurance limit exceeded per accident or shipment	Open Cover, Underwriting Limits	Obtain prior individual approval for high-value cargo

Difference between Underinsurance and Similar Systems

System	Basic Meaning	Reason for Insured's Burden	Points to Confirm	Difference from Underinsurance
Underinsurance	The sum insured is less than the insurable value	Self-insurance of the uninsured portion	Insured value, sum insured, insured ratio	Shortfall against the total value
Deductible	The insured bears a fixed amount	Deductible under the insurance contract	Amount, application unit, number of occurrences	Different from shortage of insurable value
Limit of Liability	Contractual maximum amount payable by the insurer	Contractual limit	Per accident, per transit, per storage location, or annual limit	May exceed the limit even if the insurable value is correct
Excluded Risks	Cause of loss is outside the coverage scope	Outside indemnity range	ICC, deductibles, additional clauses	Not a shortage of sum insured
Co-insurance	Multiple insurers agree in advance on a fixed share of liability	Contractual share of underwriting	Lead insurer, each insurer’s share	Planned joint underwriting, different from multiple insurance
Multiple Insurance	Several insurances overlap for the same interest	Division of liability among insurers	All policies and scope of liability	Not an insurable value shortage, but overlapping coverage

Relationship with General Average and Salvage Charges

Underinsurance may raise issues not only concerning physical damage to cargo but also in the handling of general average contributions or salvage charges.

While general average contributions are calculated based on the cargo's value, if the marine cargo insurance sum insured is insufficient relative to that value, the insurer may not cover the full contribution. As a result, the uninsured portion could become the responsibility of the insured.

Regarding salvage charges, the allocation of liability between the insurer and the insured could also be affected depending on the sum insured, the value insured, the applicable clauses, and any specific policy conditions.

It is necessary to confirm the actual scope of coverage by reviewing the applicable Institute Cargo Clauses, sum insured, insurable value, general average clauses, salvage charges clauses, and any specific policy terms.

For general average, refer to the explanation of General Average under the Marine Insurance Act 1906. For setting the sum insured, also consult related articles addressing valuation and sum insured.

Main Situations Where Subrogation, Contribution, and Underinsurance Become Issues

Situation	Relevant System	Documents for Confirmation	Purpose of Confirmation
Cargo damaged during transport	Subrogation	B/L, accident notice, survey report, receipt	To preserve claims rights against the carrier, etc.
Residual goods discovered after total loss settlement	Subrogation / Remaining Interest	Total loss adjustment sheet, remaining property inventory, sales quotation	To confirm ownership and disposal method of residual interest
Settlement proposal received from the carrier after insurance payment	Subrogation / double recovery	Settlement proposal, insurance payment details, damage amount	To confirm insurer’s approval and allocation of recovery funds
CIF insurance and buyer’s open cover overlap	Contribution	Seller’s insurance, buyer’s insurance, sales contract	To confirm whether the same insured interest is duplicated
Both trading company and cargo owner have insured the cargo	Contribution	Each insurance policy, transaction documents, name of insured	To confirm whose interest each insurance covers
Only part of the invoice is insured	Underinsurance	Full invoice, insurance notification, B/L	To confirm the uninsured proportion
High-value cargo exceeds open cover limit	Underinsurance / limit of liability	Blanket insurance policy, individual approval, cargo value	To confirm handling of amount exceeding the limit
General Average contribution requested	Underinsurance	General Average notice, insurance policy, cargo value	To confirm insurer’s and insured’s share of liability

Situations Where Immediate Determination of Subrogation, Contribution, or Underinsurance Is Not Possible

Situation	Reason Immediate Determination Is Not Possible	Additional Items to Confirm	Notes
Two insurance policies exist	They may cover different insurable interests, risks, or insured transits	Insured party, insurable interest, insured transit, covered risks	Do not determine overlapping insurance based solely on the number of policies
The insurer has approved payment of indemnity	Subrogation under Section 79 generally arises from actual payment	Date of payment, power of attorney, existence of rights transfer	Do not confuse the approval date with the date subrogation arises
There is remaining property after a total-loss settlement	Confirmation of insurer’s rights, disposal costs, and contract terms is necessary	Salvage value, storage costs, disposal conditions	The insured should not sell salvage unilaterally
Partial indemnity was received from the carrier	Treatment of recovery funds may differ before and after insurance payment	Timing of payment, total loss amount, sum insured	Always report to the insurer
Insurance amount equals the invoice value	The sum insured may include freight, insurance premium, or valuation uplift	Basis of insurance, declared value, valuation uplift	Do not judge sufficiency based solely on invoice value
The partial loss amount is less than or equal to the sum insured	Underinsurance may involve proportional self-retention	Insured value, insured ratio, applicable insurance conditions	Payment in full is not guaranteed even if the loss is within the limit

Confirmation Flow for Subrogation, Contribution, and Underinsurance

1. Confirm the insurance contract and governing law
   Verify whether the Marine Insurance Act 1906 applies, and whether domestic clauses or individual conditions modify it.
2. Organize the parties involved in the incident and their liability relationships
   Identify involvement of the maritime carrier, NVOCC, freight forwarder, warehouse operator, and cargo handling agents.
3. Collect all insurance policies
   Ensure there are no other insurance contracts covering the same cargo or insured interest.
4. Reconcile the insurable value and sum insured
   Check the invoice, freight charges, insurance premium, valuation uplift, and exchange rates.
5. Determine whether it is a total loss or partial loss
   Handling of salvage and ownership of insured items differs accordingly.
6. Preserve claims against third parties
   Manage accident notifications, Claim Letter, entries on receipts, and time bars.
7. Confirm the scope of insurance payout
   Clarify deductibles, uncovered damages, sum insured, and limits of liability.
8. Confirm the scope of subrogation
   Verify which rights the insurer acquires and under what limits of liability.
9. Separate the double-insurance test from the contribution analysis
   First confirm the same marine adventure, the same insurable interest and the aggregate sums insured. Then determine each insurer’s liability for the actual casualty by examining the covered peril, policy period, exclusions, deductibles and limits.
10. Confirm the ratio of underinsurance
    Calculate the proportion of the sum insured relative to the insurable value or policy valuation.
11. Confirm the handling of recoveries and salvaged property
    Do not settle, sell, discard, or waive rights without the insurer’s consent.
12. Consult specialists
    For high-value incidents, multiple insurances, or contentious issues under UK law, consult the insurance company, Insurance Agent, Insurance Broker, and legal experts.

Typical Problem Cases

Case	Main Issues	Reference Documents	Key Points for Judgement	Initial Actions
Residual cargo can be sold after total loss	Section 79(1), residual interest	Total loss adjustment statement, residual cargo photos, sales quotation	Scope of benefits transferred to the insurer	Confirm insurer’s instructions prior to sale
Claiming against carrier after partial loss insurance payment	Section 79(2), subrogation within payment range	Insurance payment details, Claim Letter, B/L	Portion paid by insurer vs. remaining uncovered loss of insured	Preserve the right to claim and time bar
Insured settled independently with carrier	Impairment of subrogation rights	Settlement agreement, release letter, insurance payment records	Check whether insurer’s rights have been waived	Consult insurer before signing any documents
Overlap of CIF insurance and buyer’s insurance	Section 80, insured interest	Sales contract, insurance policies of both parties, risk transfer point	Whether the same economic interest is covered by both insurances	Declare other insurances to both insurers
One insurer made full advance payment	Contribution claim	Liability amounts of each insurer, payment details	Final allocation of loss burden	Coordinate contribution settlement between insurers
Cargo value 10 million yen, sum insured 7 million yen	Section 81, underinsurance	Invoice, insurance policy, insurance notification	70% insured ratio, 30% uninsured ratio	Calculate self-retention for total and partial loss respectively
Insurance notification does not include freight charges	Underinsurance	Freight invoice, invoice, insurance valuation criteria	Amount shortfall against proper insurable value	If before the incident, confirm arrangements for increasing coverage
Uninsured portion in General Average contribution	Underinsurance, General Average	General Average notice, insurable value, sum insured	Burden ratio between insurer and insured	Confirm guarantee procedures and self-retention amount

Example 1: Discovery of Salvage after Total Loss Insurance Payment

Suppose machinery cargo was immersed in seawater due to a maritime accident, and the repair and recovery costs were so high that the insurer paid out the insurance as a total loss.

After the payment, it was found that some parts could be reused or sold.

Under Section 79(1), the insurer acquires the right to subrogate the insured’s interest in the remaining salvage for which total loss indemnity was paid.

If the insured sells the parts without notifying the insurer and retains the sale proceeds, there could be an issue of double recovery from both the insurance payout and the salvage value.

Costs related to storage, inspection, sale, and disposal of the salvage should be accounted for and handled according to the insurer’s instructions.

Example 2: When the Carrier Proposes a Settlement after Partial Loss Payment

Suppose part of the cargo is damaged during handling, and the insurer pays the insured a indemnity of 3 million yen.

Subsequently, the carrier offers the insured a settlement amount of 2 million yen.

Under Section 79(2), the insurer is subrogated to the rights the insured held against the carrier to the extent of the amount paid.

If the insured settles without consulting the insurer and signs documents that completely release the carrier from liability, the insurer may lose the ability to exercise the remaining claims.

If the insured still retains an uncovered deductible amount or uninsured loss, it is necessary to confirm how the recovery amount from the carrier will be allocated between the insurer and the insured.

The insured should report to the insurer upon receiving the settlement proposal to clarify the claimant, settlement terms, and the distribution of the recovery funds.

Example 3: Overlapping CIF Insurance and Buyer's Comprehensive Scheduled Insurance

Under CIF terms, assume the seller arranged marine cargo insurance, but the buyer's open cover also automatically covered all imported cargo.

Having two insurance policies does not automatically trigger contribution under Section 80.

It should be confirmed for whose benefit the seller’s insurance was arranged, whether the insurance policy or certificate was assigned to the buyer, and whether the buyer’s open cover covers the same interest and insured transit period.

If both policies cover the same buyer’s insurable interest in the cargo losses arising from the same incident, this constitutes overlapping insurance, and contribution between insurers may become an issue.

If each policy covers a different economic interest, multiple insurance policies on the same physical cargo do not necessarily constitute overlapping insurance in the same sense.

Example 4: When only ¥7 million is insured against a cargo value of ¥10 million

Assume the insurable value of the cargo is ¥10 million, but due to an input error in the insurance notification, the sum insured was set at ¥7 million.

In the event of a total loss of the cargo, the insurer’s liability would generally be up to ¥7 million, leaving the remaining ¥3 million as the uninsured portion borne by the insured.

If the cargo suffers a partial loss of ¥2 million, the insured proportion relative to the cargo value is 70%.

Under the basic structure of the Marine Insurance Act 1906, the treatment would be that the insurer covers ¥1.4 million, and the insured bears ¥0.6 million.

Additionally, if a deductible amount is set, the method of calculating the proportion and applying the deductible should be confirmed on the insurance policy.

Even if the loss amount of ¥2 million is within the sum insured of ¥7 million, in cases of underinsurance, full payment of the loss is not necessarily guaranteed.

Common Misunderstandings

Misunderstanding	Actual Viewpoint	Practical Notes
Once the insurance payment is made, all cargo accident procedures are completed.	The insurer may continue subrogated recovery claims against third parties.	Preserve accident documentation and claim rights even after payment.
By subrogation, the insurer acquires stronger rights than the insured.	The insurer’s claim is based on the rights the insured held.	Liability limits, exclusions, and time bars also apply.
In total loss cases, the insured can freely dispose of the remaining goods.	The insurer may succeed to the residual interest of the indemnified subject.	Check with the insurer before selling or discarding the residue.
An insurer who pays a partial loss indemnity acquires ownership of the cargo.	Section 79(2) states that ownership is not transferred to the insurer in partial loss cases.	Distinguish between cargo ownership and the right to claim against third parties.
If there are two insurance policies, it is always duplicate insurance.	First confirm the same marine adventure and insurable interest. Then determine whether the actual casualty is covered under both policies.	The seller and buyer may have different insurable interests.
The first insurer to receive a claim bears the entire final loss burden.	Section 80 may provide for contribution among insurers.	Declare other insurance policies to each insurer.
Underinsurance only becomes an issue in cases of total loss.	The insured may bear uninsured proportions even in partial loss cases.	Confirm the insured percentage relative to the sum insured.
If the loss amount is within the insurance sum insured, the full amount will be paid.	Underinsurance may result in proportional indemnity.	Check both the policy sum insured and the insurable value.
Insuring the invoice value always ensures sufficient coverage.	The insurable value may include freight, insurance premiums, loading rates, and other costs.	Confirm the underwriting basis as stipulated by the insurance contract.
There is no need to report to the insurer if recovery is made from the carrier.	Double recovery and infringement on the insurer’s subrogation rights may arise.	Always report any settlement or indemnity monies received.

Checklist for Forwarder Practice Decisions

Situation	Party to Confirm With	Points to Confirm	Actions if Issues Arise
At receipt of insurance application	Shipper	Total invoice amount, currency, freight, valuation uplift, and shipment in separate lots	Verify declared value according to insurance value calculation standards
At notification of open cover	Shipper, Insurance Agent	Cargo, sum insured, insured transit, notification date, and insurance limit	Match shipping data with the insurance notification
Upon occurrence of an incident	Shipper, Carrier, Insurer	Date/time of incident, location, cause, cargo condition, and responsible party	Issue incident notice, take photographs, arrange survey, and record on delivery receipt
When claiming against the carrier	Ocean Carrier, NVOCC	Notification deadline, Claim Letter, liability limits, and time bar	Send written notice before deadline to preserve rights
When checking other insurance	Shipper, Seller, Buyer	Other insurance policies, insured parties, insurable interest, insured transit, and covered risks	Declare potential overlap to all involved insurers
After insurance payout	Insurer	Scope of subrogation, salvage, recovery procedures, and required documents	Submit documents and cooperate with subrogation against third parties
When receiving settlement proposal from a third party	Insurer, Legal Experts	Settlement amount, release wording, waiver of rights, and allocation of recovered funds	Do not sign without insurer’s approval
If underinsurance is suspected	Shipper, Insurance Agent	Insured value, sum insured, insured proportion, and deductible	Estimate liability amounts for total loss and partial loss cases separately
When general average is declared	Insurer, General Average Adjuster	Cargo value, sum insured, General Average Guarantee, and contribution amount	Confirm guarantee method for uninsured portions and own liability amount

Stakeholders' Roles

Stakeholder	Main Role	Information to Confirm or Provide	Points of Caution
Shipper / Insured	Declare accurate insurance value and preserve rights against third parties	Invoice, accident documentation, other insurance policies, recoveries from third parties	Do not settle independently, waive rights, or dispose of salvage.
Freight Forwarder / NVOCC	Organize transportation documents, assist in accident notification and rights preservation	Booking, B/L, receipts, accident details, related parties	May also become the party receiving subrogation claims.
Insurance Agent	Confirm insurance contracts, other policies and sum insureds, coordinate with insurer	Insurance policy, coverage notifications, sum insureds, accident documents	Identify partial or overlapping insurance at an early stage.
Insurance Broker	Support policyholder side by coordinating with the market, managing contributions and recovery procedures	Slip, Policy Wording, underwriting shares of multiple insurers	Distinguish legal status from Insurance Agents.
Insurer / Underwriter	Pay claims, perform subrogation and insurer contribution settlements	Payment details, legal documents, other insurance policies, salvage	Also confirm and recover uncompensated losses of the insured.
Surveyor	Investigate cause of loss, damage amount, salvage value, and liability relationships	Photographs, inspection reports, repair estimates, salvage	May not decide final legal responsibility.
Legal Expert	Assess governing law, liability limits, claim deadlines, subrogation, and contribution	Insurance policy, B/L, accident documents, settlement proposals	Early consultation required for major claims or imminent deadlines.

Relationship with Sections 82 and Following

From Section 82 onward, the Marine Insurance Act 1906 covers provisions relating to premium refund, mutual insurance, supplementary regulations, interpretative provisions, repeals, short title, and schedules.

While these are important for a comprehensive understanding of the UK Marine Insurance Act, they generally do not arise as frequently in typical overseas cargo claims as Sections 79 to 81 do.

This article limits its scope to Sections 79 through 81, which are directly concerned with cargo claims recovery, allocation among multiple insurers, and the uninsured losses borne by the insured.

Practical Points

Regarding subrogation, it is necessary not only to consider procedures after the payment of insurance benefits but also to preserve rights against third parties immediately after the occurrence of an incident.

Notification of the incident to the carrier, Claim Letter, notification deadlines stipulated in the B/L terms, contractual or statutory time bar, surveys, photographs, receipts, and preservation of packaging materials all directly affect the insurer’s subrogation rights.

For double insurance, first apply the Section 32 test by confirming the same marine adventure, the same insurable interest and the aggregate sums insured. Then determine the scope of Section 80 contribution by examining whether the actual casualty falls within each policy’s covered perils, policy period, insured transit, exclusions, deductibles and limits.

Regarding underinsurance, comparing only the sum insured and the damage amount is insufficient. The insured percentage relative to the insurable value should be checked, and consider that there may be an insured’s contribution even in cases of partial loss.

When receiving recoveries from carriers, etc., after insurance payments, or when selling salvage, it is necessary to report to the insurer to avoid double recovery or infringement of subrogation rights.

Summary

Section 79 of the Marine Insurance Act 1906 governs subrogation, Section 80 addresses contribution in cases of double insurance, and Section 81 covers the effects of underinsurance.

In the event of a total loss, the insurer acquires the insured's residual interest in the subject matter for which total loss indemnity was paid, thereby stepping into the insured’s rights and remedies against third parties.

In the case of a partial loss, the insurer does not obtain ownership of the insured property; however, to the extent that the insured has been compensated, the insurer assumes the insured’s rights and remedies against third parties that existed at the time of the loss.

Subrogation claims commonly arise in relation to ocean carriers, NVOCCs, freight forwarders, warehouse operators, terminals, stevedores, or truck carriers.

The insured must manage loss notification, Claim Letters, evidence preservation, and limitation periods prior to the payment of insurance proceeds.

For double insurance, the parties must first establish that the policies concern the same marine adventure and the same insurable interest and that the aggregate sums insured exceed the permissible indemnity. Contribution then applies only to the extent that the insurers are contractually liable for the same actual loss.

In underinsurance, the insured is regarded as self-insuring the portion of the insurable value or declared value on the policy that is not covered by sum insureds.

Underinsurance issues can arise not only in total loss cases but also in partial losses, General Average contributions, and salvage charges, where the insured bears part of the cost.

In practice, it is important to sequentially verify protection of rights against third parties, the existence of other insurance, insurable value versus sum insured, salvage or recoveries, and limitation periods.

The handling of subrogation, insurer contribution, and underinsurance under marine insurance contracts governed by UK law varies based on the insurance policy, applicable clauses, presence of other insurance, and individual circumstances of each loss. Please consult the insurer, Insurance Agent, Insurance Broker, or legal professionals well-versed in UK law for specific cases.