Marine Insurance Act 1906, section 55

Category: Claims and policy principles · Reviewed by the Apex broking team · Last reviewed 2026-08-22 · ~5 min read

The general rule in subsection (1)

Section 55(1) provides that, subject to the provisions of the Act, and unless the policy otherwise provides, the insurer is liable for any loss proximately caused by a peril insured against, but, subject as aforesaid, he is not liable for any loss which is not proximately caused by a peril insured against.

Two features of the drafting are easy to miss. The rule is expressed in both directions — it states what is covered and what is not — and it is subject to the policy. Section 55 is a default rule; the parties may contract for something different, and in practice most modern wordings do at least in part, by defining the perils and by adding express exclusions.

Proximate cause

Section 55 codifies the principle that the law looks for the proximate, not the last or the first, cause of a loss. Proximate in this context means dominant or effective, not nearest in time. Where a chain of events leads to a loss, the question is which cause was the real and operative one; where two causes operate concurrently and one is insured and the other merely uninsured, the loss is generally recoverable, but where one of them is expressly excluded, the exclusion usually prevails. Although the section is part of a marine statute, the principle it states is the general English law of causation in insurance and is applied to property, liability and other non-marine covers as well.

That is why section 55 is quoted so often in claims correspondence that has nothing to do with ships.

Excluded losses in subsection (2)

Subsection (2)(a) deals with wilful misconduct: the insurer is not liable for any loss attributable to the wilful misconduct of the assured, but, unless the policy otherwise provides, he is liable for any loss proximately caused by a peril insured against even though the loss would not have happened but for the misconduct or negligence of the master or crew. The distinction is between the deliberate act of the assured, which is never covered, and the negligence or even misconduct of those operating the vessel, which is.

Subsection (2)(b) excludes loss proximately caused by delay, even where the delay was itself caused by a peril insured against, unless the policy provides otherwise. Subsection (2)(c) excludes ordinary wear and tear, ordinary leakage and breakage, inherent vice or nature of the subject-matter insured, loss proximately caused by rats or vermin, and injury to machinery not proximately caused by maritime perils — again, unless the policy provides otherwise.

Wilful misconduct and the wider principle

The wilful misconduct exclusion in subsection (2)(a) is the marine expression of a wider rule: a person cannot recover under a policy for a loss they deliberately brought about. Note the wording — loss “attributable to” the wilful misconduct of the assured, which is a looser causal test than the proximate cause standard applied elsewhere in the section. Note also that it is the assured’s misconduct that matters, not that of employees or contractors, unless the policy says otherwise or the acts can be attributed to the assured.

Why it matters to a commercial buyer

For anyone buying cargo, hull, freight or marine liability cover, section 55 is the backdrop against which the policy is read: the named perils and the express exclusions modify it, but where the wording is silent the section fills the gap. Inherent vice and ordinary leakage in particular are common grounds of declinature on cargo claims, and they sit in the statute rather than in the certificate, so they are easy to overlook when comparing wordings. For non-marine buyers, the value of the section is that it is the clearest statutory statement of how causation is decided when a loss has more than one candidate cause.

Frequently asked questions

Does section 55 apply to non-marine insurance?

Section 55 is part of the Marine Insurance Act 1906 and applies of its own force to contracts of marine insurance. The proximate cause principle it codifies is, however, the general English law rule and is applied across property, liability and other classes.

What does 'proximate' mean in section 55?

Dominant or effective, not nearest in time. The court looks for the real and operative cause of the loss rather than the last event in the chain.

Can a policy override section 55?

Yes, in large part. Subsection (1) and each limb of subsection (2) apart from wilful misconduct are expressed to apply 'unless the policy otherwise provides', so the wording can and often does extend or narrow the position.

Related entries

• Proximate cause
• Marine Insurance Act 1906
• Marine Insurance Act 1906: historical context
• Marine liability insurance
• Subrogation
• Commercial insurance UK

This entry is part of the Apex Insurance Wiki. It states the position as at August 2026. Last reviewed 2026-08-22. Next review: 2027-02-22. It is general insurance information, not legal advice, and it is not regulated advice on a specific policy.

Apex Insurance Brokers Limited is authorised and regulated by the Financial Conduct Authority (FRN 724952). This page is general information, not advice on a specific policy.