Loss of Chance: When You Miss an Opportunity Due to an Adviser's Mistake

By mr. Vincent Besters

The Pain of a Missed Opportunity

Imagine: you have spent months working on a promising tender procedure. Your accountant was supposed to deliver the required financial annual statements on time, but due to an error on his part, the documents are submitted late. Your bid is set aside. The contract, worth several hundred thousand euros, goes to a competitor. The opportunity was real, the damage is tangible, but the question is: would you actually have been awarded the contract? You do not know, and neither does the court. This is precisely where the loss of chance doctrine comes into play.

What Is the Loss of Chance Doctrine?

The loss of chance doctrine is a principle within Dutch damages law that offers a remedy in situations where a failure or unlawful act has led to the loss of a chance at a better outcome, without it being possible to establish with certainty whether that better outcome would actually have been achieved. In such a case, the damage does not consist of the loss of the end result itself, but of the loss of the real possibility of achieving that result.

Crucially, the chance in question must have been sufficiently real. A purely hypothetical or negligible possibility does not qualify. The Supreme Court has repeatedly emphasised that the court must assess whether the chance that was lost genuinely existed and had some substance to it. In practice, this means that as a business owner you must demonstrate that, but for your adviser's mistake, you would have had a serious chance of achieving the desired outcome.

How Does the Court Quantify the Damage?

Once a court has established that there has been a loss of a real chance, it faces a complex task: quantifying something that is by definition uncertain. Article 6:97 of the Dutch Civil Code affords the court the necessary latitude to do so. The court may assess the damage in the manner most consistent with the nature of the loss, and may estimate the amount where it cannot be established with precision.

In practice, courts typically apply a percentage-based approach. The value of the missed opportunity is determined by multiplying the probability of the chance by the magnitude of the potential loss. If you had a forty per cent chance of winning the contract and the lost profit amounts to two hundred thousand euros, the loss of chance damages may be assessed at eighty thousand euros. That probability figure is a finding of fact, based on all available circumstances: the competitive position of your business, the strength of your bid, the number of competitors and the standard award criteria.

Loss of Chance Versus Proportional Liability: Not the Same Thing

The distinction between loss of chance and proportional liability is frequently confused in practice, yet they are fundamentally different concepts. In a loss of chance case, it is clear which head of damage is at issue, namely, the loss of a chance, and that chance itself is the object of the compensation. In proportional liability, the head of damage is clear, think of personal injury or business loss, but uncertainty exists as to causation. In that situation, liability may be apportioned in accordance with the degree to which the error is likely to have contributed to the occurrence of the damage. The Supreme Court has on multiple occasions emphasised that proportional liability is an exceptional doctrine, accepted only in particular circumstances, not least because of the far-reaching consequences for the liable party.

A Recent Confirmation from The Hague

In its judgment of 20 June 2025, ECLI:NL:HR:2025:1388, the Supreme Court once again reaffirmed the principles governing the loss of chance doctrine and its relationship to the assessment of damages under Article 6:97 of the Dutch Civil Code. The judgment underlines that courts enjoy considerable freedom when quantifying loss of chance damages, but that such freedom comes with a duty to provide adequate reasoning. A court cannot content itself with a broad estimate without making transparent which factors it has taken into account in determining the probability of the chance. For business owners who suffer loss as a result of advisers' mistakes, this is significant: it compels both you and the opposing party to provide a thorough factual substantiation of the chances that were at stake.

What Does This Mean for Your Case?

The loss of chance doctrine provides business owners with a serious legal instrument where a mistake by an accountant, legal adviser or other auxiliary person has resulted in the loss of a contract, tender or other commercial opportunity. However, it requires careful substantiation. You will need to demonstrate that the chance was real, that the mistake caused the loss of that chance and what the economic value of that chance was. This calls for a considered litigation strategy and thorough file management from the very outset.

Do you have questions about agency or contractual liability?

Mr. Vincent Besters advises entrepreneurs on contract law, agency arrangements and liability issues. Feel free to get in touch for an initial consultation.

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