Waiting periods and surprising clauses in life insurance: how far art. 3 LCS reaches after Supreme Court Judgment 531/2026
Judgment 531/2026 of 9 April of the “Tribunal Supremo” —Spain's Supreme Court, hence STS— classifies as a clause limiting the rights of the insured a stipulation imposing a 90-day waiting period for myocardial infarction cover under a life insurance policy, holding it to be a surprising clause in relation to a cover expressly taken out. Being a limiting clause, it must satisfy the requirements of article 3 of the “Ley de Contrato de Seguro”, Spain's Insurance Contract Act or LCS: special highlighting and specific acceptance in writing. The decision offers an apt occasion to review the boundary between clauses defining the risk, limiting clauses and prejudicial clauses, one of the main focal points of litigation in the insurance field.
1.The case decided by STS 531/2026: a heart attack within the waiting period
STS 531/2026 starts from a set of facts that is relatively straightforward but complex in its legal implications. The insured had taken out a life insurance policy which included, among other covers, a specific cover for myocardial infarction, with a sum insured of 50,000 euros. The policy contained a clause laying down a 90-day waiting period —a “periodo de carencia”— from the entry into force of the contract, during which insured events arising from infarction were not covered. The insured event occurred within that waiting period, and the insurer refused to pay the benefit in reliance on the clause.
Both the “Juzgado de Primera Instancia” —the court of first instance— and the “Audiencia Provincial” —the provincial appeal court— upheld the insured's claim and ordered the insurer to pay the sum insured together with the late-payment interest provided for in article 20 of the Insurance Contract Act. Both instances took the view that the waiting-period clause was, by its nature, one limiting the rights of the insured and did not meet the requirements of article 3 LCS, since it had been neither specially highlighted nor specifically accepted in writing. The Audiencia Provincial further emphasised that, although the clause appeared in bold type, the pervasive use of that typographical device and the small size of the print prevented the insured from perceiving it clearly.
The insurer brought an extraordinary appeal for breach of procedure and a cassation appeal. The first was dismissed by the Supreme Court, no manifest error being found in the assessment of the evidence. The second, which turned on the classification of the clause and on the application of article 3 LCS, is the one that provides the doctrinal key to the judgment.
2.Risk-defining clause or limiting clause: the classification of waiting periods
The core of STS 531/2026 lies in the classification of the waiting-period clause either as defining the risk or as limiting the rights of the insured. The insurer argued that it was a risk-defining clause —a “cláusula delimitadora”—, in that it fixed the temporal scope of cover of a risk, and that it was therefore not subject to the formal requirements of article 3 LCS. The Supreme Court, however, rejects that contention and confirms the limiting nature of the clause.
The Chamber recalls its settled case law on the distinction between risk-defining clauses and limiting clauses. The former define the subject matter of the contract, setting out which risks are covered, in what amount, for what term and within what temporal and territorial scope. They form part of the natural content of the contract and require only a general acceptance. Limiting clauses, by contrast, restrict, qualify or modify the insured's right to indemnity once the risk covered has materialised, departing from the typical content of the contract and from the reasonable expectations of the insured. Such clauses must cumulatively satisfy the requirements of article 3 LCS: they must be drafted clearly and precisely, be specially highlighted and be specifically accepted in writing.
Applying those criteria, the Supreme Court takes the view that a clause excluding cover for myocardial infarction during the first 90 days does not merely define the risk but restricts, in a way that takes the insured by surprise, a principal cover expressly taken out. The insured has agreed an insurance policy covering myocardial infarction from the entry into force of the policy, and the introduction of a waiting period which deprives that cover of effect during the first 90 days departs from what may be regarded as the typical and expected content of the contract. The clause therefore does not define the risk but limits the insured's right to the benefit during an initial period, and must be treated as a limiting clause.
The Chamber emphasises the surprising character of the clause. In taking out a specific cover for infarction, the insured may reasonably understand that cover is in place from the moment the contract takes effect, save for clear and highlighted exclusions. A 90-day waiting period which is not presented in a particularly visible manner and is not made subject to specific acceptance may go unnoticed and frustrate the policyholder's legitimate expectations. It is that dimension of surprise which justifies the strict application of article 3 LCS.
3.The requirements of article 3 LCS: special highlighting and specific acceptance
Once the clause has been classified as limiting, the Supreme Court examines whether it satisfies the formal requirements of article 3 LCS. That provision lays down that the general and the particular conditions must be drafted clearly and precisely, that clauses limiting the rights of insured persons must be specially highlighted and that they must be specifically accepted in writing. The purpose of those requirements is to ensure that the insured has real and effective knowledge of the limitations placed on their rights and gives informed consent.
In the case of STS 531/2026, the Audiencia Provincial had found that the clause, although it appeared in bold type, was not genuinely highlighted, because the extensive use of bold type in the document diluted any effect of emphasis and because the print was small, making it difficult to read. The Supreme Court upholds that finding, noting that the highlighting must be real and effective, not merely formal. It is not enough to set the clause in bold type if the rest of the text is in bold type too, or if the typographical design prevents the insured from identifying it as a material limitation.
As to specific acceptance in writing, the Chamber finds that there was no separate signature or declaration of intent by the insured in respect of the waiting-period clause. General acceptance of the policy does not dispense with the requirement of specific acceptance of limiting clauses. The absence of such specific acceptance means that the clause cannot be relied on against the insured, who may claim the benefit as if the waiting period did not exist.
The consequence of failure to comply with the requirements of article 3 LCS is clear: the limiting clause is treated as not written, and the contract is construed as if cover for myocardial infarction had been full from the moment it took effect. The insurer must pay the sum insured, and an unjustified refusal of the benefit may give rise to the late-payment interest provided for in article 20 LCS.
4.Risk-defining, limiting and prejudicial clauses: the boundary and its effects
STS 531/2026 forms part of a line of case law which has progressively refined the boundary between risk-defining clauses, limiting clauses and prejudicial clauses. Risk-defining clauses, as noted above, specify the risk covered and form part of the natural content of the contract. Limiting clauses restrict rights and require compliance with article 3 LCS. Prejudicial clauses —“cláusulas lesivas”—, for their part, are those which, in addition to limiting rights, are contrary to good faith and cause a significant imbalance to the detriment of the insured, and may be void as unfair in contracts with consumers under the legislation on the protection of consumers and users.
The classification of a clause as risk-defining or as limiting has decisive practical consequences. If it is regarded as risk-defining, it is enough that it be drafted clearly and intelligibly, and it becomes part of the contract by general acceptance. If it is regarded as limiting, it must pass the filter of article 3 LCS, and formal non-compliance makes it unenforceable against the insured. The category of the surprising clause, used by the case law to refer to stipulations which, without being openly unfair, depart from the reasonable expectations of the insured, has served to reinforce the requirement of transparency and of highlighting in limiting clauses.
Waiting periods lie in a particularly sensitive area of that boundary. In some classes of insurance, such as sickness or healthcare insurance, the waiting period may be regarded as part of the typical content of the contract, provided that it is presented clearly and responds to a technical rationale of risk selection. In others, such as life insurance with specific covers for death or disability from particular causes, the introduction of waiting periods in respect of principal risks expressly covered may prove surprising and therefore limiting. STS 531/2026 comes down in favour of the second view in the case of myocardial infarction, emphasising that the waiting period affects a central risk of the contract and that, without specific highlighting and specific acceptance, it frustrates the legitimate expectations of the insured.
The category of the prejudicial clause may come into play where the waiting period, besides being limiting, proves disproportionate or empties the cover of content for an excessive period, or where it is combined with other limitations which, taken together, leave the insured practically without protection. In such cases, in addition to unenforceability for failure to comply with article 3 LCS, nullity on grounds of unfairness might be raised in contracts with consumers, on the basis of consumer legislation and of the doctrine on unfair terms.
5.The practical implications of STS 531/2026 and future litigation
STS 531/2026 has significant practical implications beyond the particular case. First, it sends a clear message to insurance undertakings as to the need to treat waiting periods affecting principal covers as limiting clauses, subject to the requirements of article 3 LCS. It is not enough to include them in the general or the particular conditions; they must be highlighted in a real and effective manner and made subject to specific acceptance in writing. Typographical design, the structure of the document and the way it is presented to the customer acquire legal relevance.
Second, the judgment strengthens the position of insured persons in disputes over waiting periods and temporal exclusions. Insured persons may challenge the enforceability of such clauses where they affect principal risks and have not been specially highlighted or specifically accepted. Evidence of the pre-contractual information supplied, of the way the policy was presented and of whether or not there was specific acceptance will be central in such disputes.
Third, the decision helps to clarify the boundary between risk-defining clauses and limiting clauses, offering criteria that may be applied to other devices, such as deductibles, sub-limits, exclusions for particular activities or occupations, and temporal limitations of cover. The notion of the surprising clause, understood as one that departs from the reasonable expectations of the insured in respect of a principal cover, is consolidated as a relevant interpretative criterion.
Finally, STS 531/2026 arises in a context of a high volume of litigation over transparency and the substantive review of pre-formulated clauses in insurance contracts. The distinction between risk-defining clauses, limiting clauses and prejudicial clauses will remain one of the main sources of dispute, and article 3 LCS will continue to play a central role as an instrument for the protection of the insured. Waiting periods, particularly in life and disability insurance, are placed under enhanced scrutiny, and their validity and enforceability will depend to a large extent on insurance undertakings accepting the need for real transparency and for genuinely informed consent.
