Amending a contract mid-term (section 136) – a B2G seller's guide to additional sales without a new tender
Once the public tender has been won and the contract signed, many consulting and software sellers run into the rigidity of the B2G market: the customer would like to buy new features, expand the service or get additional training, but the buyer is afraid of a new tender.
As a rule, a public procurement contract may not be materially changed during the contract period without a new procurement procedure. Section 136 of the Procurement Act does, however, contain an exhaustive list of exceptions that allow flexibility and, from the seller's point of view, additional sales during the contract period.
A bidding company needs to know these mechanisms so that it can actively help its customer make additional purchases lawfully. Here are the most important routes to additional sales that the law allows.
1. Low-value changes (the de minimis rule)
The easiest and administratively lightest way to sell additional services is to use the low-value change rule the law allows.
A procurement contract can be changed without a new tender if the value of the change stays below two limits at the same time:
- The value of the change is below the EU threshold.
- In goods and services procurement the value of the change is less than 10 per cent of the original contract value (less than 15 % in works contracts).
This means that if you have sold a software package for €500,000, you can sell the customer up to €49,999 worth of customisation, add-ons or expert work mid-term without heavy justification, as long as the nature of the original contract does not change.
2. Options and contract terms – building additional sales in advance
The most professional way to secure additional sales is to settle the matter before the original tender. The law permits contract changes and additional purchases if they were clearly announced in the original tender documents.
This is a typical scenario in software and consulting sales:
- Options: The tender documents include options that let the buyer later extend the system with new modules or add expert hours at a set price.
- Price adjustment clauses: The contract contains a clear clause (indexation, for example) that allows prices to be adjusted during the contract period.
The bidder's strategic task is to influence the customer in the market dialogue so that the contracting authority knows to build sufficient options into the tender documents for future needs (technological development or updates required by legislative changes, for example).
3. Necessary additional deliveries and technical lock-in
Another significant route to additional sales covers situations where the customer must buy more but changing supplier is in practice impossible.
Under the law, the original supplier can make additional deliveries if changing supplier:
- Is impossible for economic or technical reasons (compatibility with existing hardware, interfaces or closed-source software, for example).
- Would cause the contracting authority significant inconvenience or substantial duplication of costs.
Condition: The value of additional deliveries made on this basis may not exceed 50 per cent of the original contract value.
In software sales this is a classic situation: once the core system has been installed and integrated into the customer's infrastructure, putting a new feature out to tender with an outside provider would cause massive compatibility problems and integration costs. The seller can then lawfully offer the extension as an additional delivery under the original contract.
4. The ban on material changes – where is the line?
Although the law offers flexibility, a seller also needs to understand when a change goes too far and turns into an unlawful direct award.
A change is considered material (and therefore unlawful) if:
- The change significantly extends the contract to services or products the original tender did not cover (you cannot sell financial management software under an HR system contract).
- The change shifts the economic balance of the contract in the supplier's favour in a way not present in the original contract (transferring risk to the buyer or a huge unjustified increase in unit prices, for example).
- Changing the terms would, in the original tender, have allowed other bidders to take part or a different bid to be chosen.
Summary for the seller
When you know the rules in section 136, you can act for the customer as an adviser as well as a seller. When a customer hesitates to order an additional service for fear of a tender, a knowledgeable B2G seller can analyse the situation and propose the right legal basis — the de minimis rule or a necessary additional delivery arising from technical compatibility — so the deal can be closed with light administration and fully to the letter of the law.
Frequently asked questions
May a public procurement contract be changed during the contract period?
Material changes may not be made without a new procurement procedure. Section 136 of the Procurement Act does, however, contain an exhaustive list of exceptions that make changes and additional purchases lawful.
What is the de minimis rule in contract changes?
A change is allowed without a new tender if its value is below the EU threshold AND, in goods and services procurement, less than 10 % (less than 15 % in works contracts) of the original contract value — and the nature of the contract does not change.
How is the possibility of additional sales secured in advance?
By building options and price adjustment clauses into the original tender documents. A bidder should influence this in the market dialogue before the tender.