FoundationsCore

Utmost Good Faith

Q: What is the usual consequence of a material non-disclosure discovered after a large loss?

The reinsurer may avoid the whole contract from inception — A material non-disclosure can void the contract from its start date, not merely reduce or delay the one claim it relates to.

Uberrimae fidei

The duty on both parties to disclose every fact material to the risk, honestly and completely, before the contract is agreed.

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Definition

Utmost good faith (uberrimae fidei) is the doctrine that insurance and reinsurance contracts are built on full, honest disclosure rather than arm's-length bargaining. The cedent must disclose every fact a prudent reinsurer would want to know before quoting — adverse loss history, known exposures, anything that would change the price or the decision to write the risk — and the duty runs both ways. A material non-disclosure, even an innocent one, can let the reinsurer avoid the contract entirely.

The duty applies most strictly at inception and at each renewal, when the reinsurer is deciding whether and how to price the risk.
Materiality is judged by what would influence a prudent reinsurer's judgment, not by what the cedent personally believed was important.
A breach can let the reinsurer avoid (rescind) the whole contract from inception, not just decline the one claim affected by the non-disclosure.

Worked example

A cedent renewing its casualty treaty knows of a large asbestos-related claim developing against one insured but does not mention it in the renewal submission. When the claim later reaches the treaty, the reinsurer discovers the omission and avoids the contract — leaving the cedent with no recovery at all, not just a reduced one.

Scenario · figures in USD

A non-disclosure unwinds a whole treaty

Meridian Casualty renews its excess-of-loss layer. Its underwriters know a large product-liability claim is developing but leave it off the renewal submission because it has not yet been formally reserved.

Premium paid for the renewed layer	$1.2M
Claim that later attaches to the layer	$14M
Recovery Meridian expected	$14M
What the reinsurer discovers on investigation	The claim was known but undisclosed at renewal
Reinsurer's response	Avoids the treaty from inception
Recovery Meridian actually receives	$0

So whatUtmost good faith is not a formality — a material fact withheld, even unreserved or informal, can cost the cedent the entire recovery, not just the one claim.

Check your understanding

Why does the duty of utmost good faith fall more heavily on the party seeking cover than on an ordinary commercial buyer?

Because the reinsurer usually cannot inspect the risk itself and must rely on what it is told. Unlike a buyer inspecting goods before purchase, a reinsurer prices a risk almost entirely on the cedent's own representations, so the law places the disclosure burden on the party with the information.

What is the usual consequence of a material non-disclosure discovered after a large loss?

The reinsurer may avoid the whole contract from inception. A material non-disclosure can void the contract from its start date, not merely reduce or delay the one claim it relates to.

Word problem

A cedent's submission omits a large claim its underwriters knew about but had not yet formally reserved. The treaty later pays out $8M against that same exposure before the omission is discovered. What can the reinsurer do, and why does "not yet reserved" not excuse the cedent?

Show a hint

Materiality is judged by what a prudent reinsurer would want to know, not by the cedent's own internal reserving status.

Reveal the worked answer

The test for disclosure is materiality to the reinsurer's pricing decision, not whether the claim had cleared the cedent's own reserving process.
Underwriters "knowing about" a developing claim is itself a fact a prudent reinsurer would want disclosed, reserved or not.
Because the omission is material and known, the reinsurer can treat it as a breach of utmost good faith.
Its remedy is to avoid the treaty from inception — meaning it can decline the entire $8M already paid or claimed, not just cap it.

The reinsurer can avoid the treaty from inception and decline the full $8M, because the duty of disclosure turns on materiality to its pricing decision — not on whether the cedent's own books had formally reserved the claim yet.