What is a Contract Modification?
A contract modification in procurement law refers to the subsequent change of an already awarded public contract. § 132 GWB strictly regulates when modifications are permissible without a new procurement procedure.
Permissible Modifications
Review clauses (clearly provided in tender documents), additional services (unforeseeable, no contractor change possible, value below 50%), unforeseeable circumstances, subcontractor changes, and minor modifications (below 10/15% of contract value).
Substantial Modifications (Impermissible)
A modification is substantial and requires new procurement when it would have admitted other bidders or changed the outcome, shifts the economic balance, considerably extends the scope, or replaces the contractor.
De Minimis Thresholds
Modifications below 15% (works) or 10% (supplies/services) of contract value AND below the EU threshold are always permissible.
Practical Tip
Contract modifications are frequently reviewed in procurement disputes. Patterno also informs you about modification notices that may indicate new business opportunities.