Joinder of Third Parties in Procurement Review 2026

Definition: Joinder is the procedural inclusion of a third party – regularly the presumed successful tenderer – in ongoing review proceedings before the procurement chamber, in order to protect their legal interests and grant them the right to be heard.

Last updated: January 2026 · Legal status: § 162 GWB (Germany), § 342 BVergG 2018 (Austria)

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What is joinder?

Joinder ensures that, in procurement review proceedings, all parties whose legal interests are affected by the procurement chamber's decision can take part in the proceedings and safeguard their rights.

When an unsuccessful tenderer files an application for review before the procurement chamber, three parties are typically affected: the applicant (the challenging tenderer), the respondent (the contracting authority) and the tenderer who is to receive the contract (the so-called presumed successful tenderer). The latter is not automatically a party to the proceedings but has an obvious interest in the outcome. Joinder formally brings them into the proceedings.

Conditions for joinder

The procurement chamber joins a third party where their interests are likely to be substantially affected by the decision.

In Germany, § 162 GWB governs joinder in procurement review proceedings. To be joined:

• Undertakings whose interests are substantially affected by the procurement chamber's decision (mandatory joinder)
• Undertakings with an interest in the outcome (discretionary joinder, at the chamber's discretion)

The presumed successful tenderer is regularly joined as a mandatory party, since a decision finding the review application well-founded would directly affect their contractual position.

Rights of the joined party

Upon joinder, the joined party acquires extensive procedural rights to safeguard their interests in the review proceedings.

The joined party has the right, in particular, to:

• Inspect the files (insofar as confidentiality interests do not preclude this)
• Submit statements and applications
• Take part in oral hearings
• Lodge an immediate appeal against the procurement chamber's decision with the competent Higher Regional Court

In effect, the joined party becomes a fully fledged party alongside applicant and respondent, even though detailed procedural rights may vary slightly.

Joinder in Austria

In Austrian procurement law, joinder is enshrined in the federal-state rules on procurement review and in the BVergG 2018.

The Austrian Federal Procurement Act 2018 and the respective federal-state procurement acts provide that the Federal Administrative Court and the competent regional administrative courts may admit third parties with a legal interest in the outcome of the proceedings as parties. The presumed successful tenderer may join the proceedings to defend their interests.

Practical significance

For a joined tenderer, active participation in review proceedings is critical to averting the impending loss of the contract.

If a joined tenderer remains passive, the procurement chamber may grant the application without sufficient consideration of their counterarguments. They should therefore seek legal advice and actively engage with the applicant's arguments.

FAQ

Must a tenderer apply for joinder? No, the procurement chamber decides on joinder ex officio. However, a potentially joined tenderer should bring their interest to the chamber's attention if they learn of the proceedings.

Can a joined party lodge an appeal independently? Yes. The joined party may lodge an immediate appeal against the procurement chamber's decision with the competent Higher Regional Court independently of the applicant and respondent.

What happens if the joined party does not participate in the hearing? Proceedings continue without the joined party. Non-attendance may, however, mean that their arguments are not taken into account.

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Last updated: January 2026 All information without warranty. For legally binding advice, please consult a law firm specialising in procurement law.