The three parts at a glance
| Part | Governs | Operates | Binds |
|---|---|---|---|
| VOB/A | procurement of construction works | before contract | public clients |
| VOB/B | contract conditions | from contract | anyone incorporating it |
| VOB/C | technical conditions and measurement | from contract | anyone incorporating it |
The last column contains the most frequently overlooked point. It separates procurement law from contract law, and thus two quite different grounds of obligation.
| Part | Whom it binds | Legal ground |
|---|---|---|
| VOB/A | only public clients | procurement law; a private client need not observe its tendering rules |
| VOB/B and VOB/C | anyone incorporating them | contract conditions applying by agreement, not by force of law; a private client is then fully subject to their measurement rules |
The VOB is not a statute
This point has practical consequences beyond the system. It governs, among other things, which edition applies in a dispute.
The VOB is prepared by the German procurement and contract committee for construction works, a body of representatives of public clients and the construction industry. It is published in the federal gazette.
Three points follow, and all three are regularly underestimated in practice. They concern the binding force, the incorporation and the governing edition.
| Consequence | What it means in practice |
|---|---|
| The VOB/A becomes binding through budget law and administrative rules | not through force of its own; federal and state governments set the value thresholds for the routes themselves, and they vary considerably |
| The VOB/B and VOB/C are standard terms of business | they apply only where validly incorporated into the contract |
| References in state legislation can go stale | a state procurement act may refer to an edition of the VOB/A long superseded |
Incorporation is covered in the article on agreeing the VOB/B. Anyone working in a particular state checks the state-law reference alongside the current VOB.
The VOB/A: procurement
The VOB/A governs how public clients must procure construction works. It is divided into sections differing by contract value and field.
| Section | Scope |
|---|---|
| Section 1 | national procurement below the EU thresholds |
| Section 2 | procurement at or above the EU thresholds, marked EU |
| Section 3 | defence and security procurement, marked VS |
The classification governs the whole procedure: procurement routes, periods, publication and legal protection all differ considerably. The article on above and below EU thresholds covers the classification, and the article on the structure of the VOB/A its internal arrangement.
The VOB/B: the contract
The VOB/B contains the general conditions for executing construction works. It governs the relationship between client and contractor after contract.
Its principal areas for the cost side:
| Area | Content |
|---|---|
| Payment and variations | changed and additional work, quantity changes |
| Construction periods | hindrance, delay, consequences |
| Handover | forms, effects, start of limitation periods |
| Measurement and final account | joint measurement, verifiable invoice |
| Defect claims | periods, rights, security |
| Termination | conditions and settlement |
The branch on the construction contract under VOB/B covers the provisions material to cost work. It also sets out which periods run from handover.
The VOB/C: technical conditions and measurement
The VOB/C contains the general technical conditions of contract, the ATV. It comprises 65 standards published as DIN standards.
For cost work it is the most important part, because it answers two questions the specification does not: what is included in the price, and how measurement proceeds. Both answers act directly on the final account.
The branch on the VOB/C covers its structure, its hierarchy and the measurement rules in detail. It also sets out how incidental services are distinguished from special services.
How the three parts interlock
An example shows the interlocking more clearly than any system diagram. A single item in a bill of quantities is touched by all three parts at once.
| Part | What it determines about the same item |
|---|---|
| The VOB/A | how it must be worded so that all tenderers understand it in the same sense and can price it without extensive preliminary work |
| The VOB/C | which incidental services the tenderer must price without them appearing in the text, and in what unit measurement will later be taken |
| The VOB/B | what applies if the work changes, how handover proceeds and how the final account is built |
Knowing only one part means regularly overlooking what the other two govern. The commonest case is the item that appears fully described but contains an additional service under the VOB/C that was never tendered.
The status of the rules
All three parts are maintained, on differing cycles. There is therefore no such thing as a common edition of the three.
The VOB/A has been amended repeatedly, most recently with effect from 1 January 2026 on the thresholds for procurement routes. A wider revision in the wake of the procurement acceleration act has been announced.
The VOB/C is revised at multi-year intervals, and not for all ATV at once. The applicable edition therefore belongs in the preliminaries to the bill of quantities.
A simple rule follows: the governing edition of each part belongs named in the contract. Without it, a dispute requires establishing which version was meant, and that determination regularly falls against whoever relies on a particular provision.
Related articles
This article reflects the position of the rules at the date of checking and serves professional orientation. It does not constitute legal advice and does not replace assessment of the individual case.