A Bundestag report says German public authorities can legally specify open-source software in tenders under certain conditions, strengthening digital sovereignty while helping prevent vendor lock-in.
Germany’s Bundestag Scientific Service has concluded that public authorities can legally require open-source software (OSS) in public tenders under specific procurement law conditions, overturning the widespread belief that doing so unfairly discriminates against proprietary software vendors.
The report states that authorities may restrict procurements to OSS when there is an objective, contract-related reason, such as improving IT security, ensuring interoperability with existing systems, or preserving the ability to independently develop and maintain software. Under EU procurement rules, authorities must generally include an “or equivalent” clause unless they can demonstrate that no suitable proprietary alternative exists.
The findings also draw on recent European Court of Justice (ECJ) rulings, including decisions from January 2025, which challenged vendor lock-in practices. The court held that public bodies cannot justify direct follow-on contracts solely because they became dependent on a proprietary supplier through earlier procurement decisions. Instead, authorities should monitor the market, plan procurement strategically from the outset and avoid creating anti-competitive exclusivity.
According to the report, choosing OSS or securing comprehensive source-code usage rights is often not only economically beneficial but may also be necessary to prevent monopolistic dependence. For contracts below EU procurement thresholds, lower licensing costs and reduced migration expenses can make OSS the more economical choice. The findings strengthen the policy case for open source as a foundation for digital sovereignty and could encourage wider OSS adoption across European public-sector procurement.
