cooperation.law

Acting together binds us.

Contract for work

The question

What does it mean for cooperation when a result, not simply work, is owed?

In brief

Under a contract for work (Werkvertrag) the contractor promises a result, not merely an effort (Section 631 German Civil Code (BGB)). Yet the result rarely comes about without the client, who must clarify requirements, supply information, review interim stages and finally accept the work. The law reflects this interplay, from participation (Section 642 BGB) and acceptance (Section 640 BGB) to the priority of cure when there are defects.

The law

Result for remuneration

Under a contract for work the contractor is obliged to produce the promised work and the client to pay the agreed remuneration (Section 631(1) BGB). The subject may be the making or alteration of a thing, or another result to be brought about by work or services (Section 631(2) BGB): a made-to-measure cupboard as much as an expert opinion, a website or bespoke software.

What distinguishes it from the service contract is who bears the risk of success. A service contract pays for the activity, a contract for work for the result. Contracts to manufacture and deliver movable goods, by contrast, are in principle governed by the law of sale (Section 650(1) BGB).

The first joint act is describing the work. The more precisely client and contractor agree on what is to be created, the fewer disputes about defects later. Where requirements only emerge as the work proceeds, as in agile software development, the model of a fixed work fits only partly, and how such projects should be classified is disputed. All the more reason for the contract to say how requirements are set and changed. See the change procedure on the page Cooperative clauses.

The client’s participation

Many works depend on the client: access, data, plans, decisions, approvals. If such an act is required and the client, by failing to perform it, is in default of acceptance, the contractor may claim reasonable compensation (Section 642(1) BGB). The contractor may also set a reasonable deadline and declare that the contract will be terminated if the act is not performed; once the deadline passes, the contract is deemed cancelled (Section 643 BGB).

Under the statute, participation is in principle a burden on the client, not an enforceable duty. The contract can change that. For construction contracts, the Federal Court of Justice has also recognised a general duty to cooperate (BGH, judgment of 28 October 1999 – VII ZR 393/98, BGHZ 143, 89), and Section 650b BGB requires the parties to seek agreement when changes are requested. See Cooperation as a legal relationship.

Acceptance

The client must accept work produced in conformity with the contract, unless acceptance is excluded by the nature of the work, and may not refuse acceptance on account of insignificant defects (Section 640(1) BGB). Acceptance means that the client approves the work as essentially in conformity with the contract.

On acceptance the remuneration falls due (Section 641(1) BGB), the risk passes to the client (Section 644 BGB) and limitation of claims for defects begins (Section 634a(2) BGB). If the contractor sets a reasonable deadline for acceptance after completion and the client does not refuse, stating at least one defect, the work is deemed accepted. Against a consumer this applies only if the contractor pointed out this consequence in text form together with the request (Section 640(2) BGB).

Acceptance also shifts the burden of proof: from then on it is, as a rule, for the client to prove that the work is defective. That is a reason to go through the work together before accepting it. Parties who have checked it together argue less later about what was delivered.

Defects and the priority of cure

The work must be free from material defects and defects of title (Section 633 BGB). If it is defective, the client may demand cure, remedy the defect and claim the costs, withdraw or reduce the price, and claim damages or reimbursement of wasted expenses (Section 634 BGB).

These remedies are not of equal rank. Self-remedy, withdrawal, price reduction and damages in lieu of performance generally require the client first to have set the contractor a reasonable deadline for cure without success (Sections 637, 636, 323, 281 BGB). The law thus gives the contractor the first chance to make the work conform after all. The contractor chooses how, by repairing the defect or producing a new work (Section 635(1) BGB). Whoever created the work is to decide how it is put right.

Termination

The client may terminate the contract at any time until the work is completed; the contractor then keeps the agreed remuneration less expenses saved and earnings from other use of the contractor’s capacity (Section 648 BGB). Either party may terminate for a compelling reason if continuing to completion is unreasonable (Section 648a BGB).

Online

Software development is now often carried out entirely online; whether as a contract for work depends on what is owed (see above). The parties work together in a repository, a ticket system and video calls, often without ever meeting on site.

Participation. Online, the work often hinges on things only the client can provide. Access, test data and reachable contacts are acts of participation. If they are missing, the contractor should say so promptly and traceably, since in a dispute the contractor must show the default of acceptance.

Acceptance. Acceptance can be declared by email or in a shared record. It can also be implied, for instance where the client puts the software into productive use after a test period without complaint. An agreed acceptance procedure with a test environment, test cases and a deadline is clearer.

Consumers. Where a business undertakes towards a consumer to produce digital content or to bring about a result by a digital service, Sections 633 to 639 BGB on defects and Section 640 BGB on acceptance do not apply (Section 650(2) BGB). The rules on digital products take their place (Sections 327 et seq. BGB).

Consultancy online. Advice can be a work where a specific result is owed, such as an expert opinion or a concept. Where the advice itself is owed as an activity, the rules of the service contract apply.

Relevant phases

Limits of this overview

This page outlines the German Civil Code’s rules on contracts for work. Additional rules apply to construction contracts, consumer construction contracts and architects’ contracts (Sections 650a et seq. BGB) and are not covered here.

As at 30 September 2026