The no oral modification clause (geen mondeling wijzigingsbeding) under Dutch law
A no oral modification clause, commonly referred to as a NOM clause, is a standard boilerplate provision in Dutch commercial contracts stipulating that the agreement may only be amended by a document signed by both parties, and that any oral modification, however clearly agreed, is without effect. While NOM clauses are consistently enforced by Dutch courts, they are not absolute: the requirements of reasonableness and fairness embedded in Dutch contract law can, in exceptional circumstances, prevent a party from relying on a NOM clause to deny the validity of a modification it has encouraged or accepted in practice.
What is a no oral modification clause and why does it matter?
A NOM clause protects the integrity of the written agreement by preventing either party from arguing that informal communications, emails, phone calls, or verbal exchanges, have amended the contract's terms.
In practice, long-term commercial relationships generate a constant stream of operational communications: price adjustments discussed on calls, delivery schedules changed by email, payment terms extended informally. Without a NOM clause, a party may argue that these exchanges amount to a binding amendment of the underlying contract. A well-drafted NOM clause prevents this by requiring all modifications to follow a defined written procedure.
Dutch commercial contracts, including share purchase agreements, distribution agreements, and joint venture contracts, routinely include NOM clauses alongside other boilerplate provisions such as entire agreement clauses and non-waiver clauses. Together, these clauses form a protective framework around the written terms of the contract.
What are the limits of a NOM clause under Dutch law?
Under Article 6:248(2) of the Dutch Civil Code, a contractual provision, including a NOM clause, may not be applied where doing so would be unacceptable according to the standards of reasonableness and fairness in the circumstances.
Dutch courts apply a high threshold before overriding a NOM clause on this basis. Merely showing that an oral modification was agreed, or that one party subjectively believed it was agreed, will not suffice. The party seeking to enforce the oral modification must demonstrate that it acted in justified reliance on the modification, that the other party was aware of and acquiesced in that reliance, and that strict application of the NOM clause would produce a result that no reasonable person could expect to be enforced.
This standard is demanding, and Dutch case law shows that courts are generally reluctant to set aside a clear written provision on the basis of informal conduct. Nevertheless, the possibility cannot be excluded in cases of clear and repeated acquiescence by one party in a modification that the other party has acted upon at significant cost. Practitioners should therefore not treat a NOM clause as a guarantee against oral modification claims, but as a strong evidential and legal starting point.
What is a double NOM clause (dubbele NOM-clausule) and when is it used?
A double NOM clause adds a second layer of protection: it provides that not only must amendments be in writing, but also that the NOM clause itself cannot be waived except in writing, closing the argument that the parties orally agreed to set the NOM clause aside before amending the contract.
The single NOM clause creates a logical gap: if the parties have orally agreed to set the NOM clause aside, the subsequent oral modification may be argued to be valid. The double NOM clause addresses this by treating any purported oral waiver of the NOM clause as itself invalid. In Dutch M&A practice and high-value commercial contracts, double NOM clauses have become the preferred drafting standard because they eliminate this residual vulnerability.
Even with a double NOM clause, the Article 6:248(2) standard remains technically available. However, the double structure makes it considerably harder for a party to construct a credible argument that the NOM clause was effectively waived, since any such waiver would itself need to comply with the writing requirement.
How do NOM clauses operate in Dutch M&A and complex commercial transactions?
In M&A transactions governed by Dutch law, NOM clauses are a standard component of the boilerplate section of a share purchase agreement and are typically reinforced by the entire agreement clause and the non-reliance clause.
In the M&A context, the NOM clause plays a specific role during the period between signing and closing, when the parties may be in frequent communication about transition matters, pre-closing covenants, and completion accounts. Any agreement reached during this period that the parties intend to be binding as an amendment to the SPA must be documented in a signed written amendment to avoid disputes. Where parties communicate informally during this period, the NOM clause, if properly drafted, prevents those communications from being characterised as amendments.
NOM clauses also interact with the non-reliance clause: a party that has received a representation outside the written contract cannot rely on it to claim an amendment or additional warranty obligation. The combination of the NOM clause, the entire agreement clause, and the non-reliance clause creates a robust contractual framework that limits the scope for post-signing disputes about what was and was not agreed.
What practical drafting guidance applies to NOM clauses under Dutch law?
When drafting a NOM clause for a Dutch commercial contract, practitioners should consider adopting the double NOM structure, specifying the signing requirement clearly, and ensuring that the clause is consistent with the entire agreement and non-waiver provisions in the same contract.
A typical double NOM clause in Dutch practice reads as follows: "This agreement may only be amended or supplemented by a written instrument signed by authorised representatives of both parties. No oral agreement, representation, or conduct shall constitute an amendment to this agreement, and this clause may not itself be amended or waived except by a written instrument signed by both parties." Clarity as to what constitutes a valid written amendment, whether an email exchange suffices, or whether a formal signed document is required, is also worth addressing explicitly, particularly for operational agreements where email amendments are common practice.
A contract lawyer in the Netherlands can advise on the drafting of NOM clauses and the wider boilerplate framework, as well as on the risk assessment where one party believes an oral modification may have occurred in a contract governed by Dutch law.