A short claims history does not automatically mean an insurance protocol is reliable. On the other hand, a long claims record does not equal more reliability either. What you need to look at is the quality of the claims: what was covered, what was not, and why.
Nexus Mutual is currently the leading DeFi insurance protocol, managing a capital pool of around $150 million. It has paid out over $18 million in claims. Its case history itself can answer the question "How to tell if an insurance protocol is reliable."
Direction 1: Check the Coverage Scope, Not Just the Payout Amount
Nexus Mutual's paid claims cover three typical scenarios:
- Smart contract bugs: TribeDAO and Rari Capital incident paid $5.08M, Euler $2.39M, Yearn $2.32M
- Custodian withdrawal halts: In events like FTX, BlockFi, Gemini Earn, and Hodlnaut, Nexus Mutual paid out $4.9M within three months of FTX halting withdrawals
- Protocol-level contagion risk: In 2025, the Stream Finance collapse caused bad debt in multiple Beefy and Harvest Finance vaults. The Claims Committee eventually deemed the claims valid and approved payouts
Direction 2: Look at Rejected Claims—Understanding "What Is Not Covered" Matters More
Another side of reliability is what the protocol refused to pay. A claim related to Goldfinch was rejected because the loss came from a credit default on an undercollateralized loan, and the policy terms explicitly excluded credit risk. Such rejections are not evidence of an "unreliable protocol"—if the terms are clear and enforced consistently, it actually shows the claim boundaries are predictable. Users need to use this history to judge whether their own risk is truly within the coverage scope.
Risk note: A low historical payout ratio does not mean payouts are easy. Nexus Mutual claims are evaluated by the Claims Committee, which has a built-in bias to reject. Assessors stake NXM tokens, and approving a claim burns their staked tokens, creating an economic incentive to deny claims. Also, after submitting a claim, there is a 14-day cooling-off period, so payouts are not instant.
Direction 3: See If the Capital Pool Can Withstand Extreme Risks
This is the core dimension of reliability. Nexus Mutual's capital pool is about $150 million, but industry risk analysis points out: if the same bug hits five or more covered protocols at once, this pool could be drained, and payouts might be cut to 50–70 cents on the dollar. A single Kelp DAO event caused a $292 million loss—16 times the total claims Nexus Mutual has paid in seven years. This number alone shows the gap between the capital pool and the real risk volume.
Next Steps
When evaluating an insurance protocol, look for two things in its official documentation: a claims history list (showing which events were paid and which were rejected) and a comparison between the capital pool size and the total coverage amount (to see if it can cover extreme scenarios). Nexus Mutual's Claims History page provides a case study for each claim, helping you understand the exact payout criteria. If you plan to insure a specific protocol, first search its claims history to see whether that protocol has been paid or rejected before. This is more useful than looking at the total amount paid.
