Non-waiver clauses: safeguarding against implied waiver of rights

Gepubliceerd op 12/08/2025

In commercial contracts, the non-waiver clause is increasingly common. This clause (known in Dutch as ‘niet-verzakingsclausule’ and in French as ‘clause de non-renonciation’) regulates the consequences of a complete or partial failure or delay in exercising one or more contractual rights.

But how does this clause operate under Belgian law?

What is a non-waiver clause?

A non-waiver clause stipulates that the failure or delay in exercising a contractual right does not constitute a waiver of that right. Typical formulations include:

“The failure or delay in exercising any right or remedy under this Agreement shall in no event be construed as a waiver of such right.”

This clause provides protection against implied waiver, a unilateral legal act whereby a party relinquishes its right without an explicit declaration.

Waiver of rights vs. forfeiture of rights

Belgian law recognizes two related grounds for the extinction of obligations:

• Waiver of rights (afstand van recht in Dutch): a unilateral legal act whereby a creditor, through an expression of will, intends to extinguish the (claim) right arising from an obligation. The legal consequence is significant: by waiving the right, the obligation is irrevocably extinguished and the debtor is definitively released.
• Forfeiture of rights (rechtsverwerking in Dutch): requires conduct that is objectively incompatible with the exercise of the right and creates a legitimate expectation in the counterparty that the right will not be exercised.

A non-waiver clause may exclude the application of waiver of rights, but cannot automatically exclude forfeiture of rights, as the prohibition of abuse of rights is a matter of public policy.

Usefulness and limitations

Although Belgian law already imposes strict conditions for recognizing implied waiver of rights, a non-waiver clause can provide additional legal certainty. It allows parties to temporarily deviate from their rights (e.g., to seek a commercial resolution) without risking permanent loss of those rights.

However, caution is advised: a party invoking the clause after prolonged tolerance may be guilty of abuse of rights. Courts retain discretion to assess such situations.

 Tailored drafting

 The added value of a non-waiver clause depends heavily on its wording. A mere reference to inaction is often redundant. A broader formulation excluding other forms of conduct as evidence of waiver is preferable. For example:

“No conduct, omission, or form of tolerance by the Service Provider shall be construed as a full or partial waiver of the right to strict and complete compliance with the contractual provisions.”

 Final considerations

A non-waiver clause is not a panacea, but it is a useful tool in the contractual arsenal. With thoughtful drafting and application, it can enhance legal certainty without undermining fundamental principles such as the prohibition of abuse of rights.

If you are uncertain about the appropriate approach, do not hesitate to seek legal advice. Our team of specialized lawyers is happy to assist you in taking the right steps.