Founding Partner at Greenfield Capital
Check size: No personal check-size range is published. Greenfield's venture strategy invests from pre-seed through later rounds; its EUR 135 million Fund III size and portfolio financing totals are not Sebastian's personal check parameters.
Sebastian backs open, decentralized infrastructure that removes single points of failure and gives users and institutions resilient alternatives to concentrated cloud, communications, identity, and financial systems. His current thesis treats privacy, self-sovereign asset management, encrypted computation, and machine infrastructure as commercially important layers of European digital sovereignty rather than speculative crypto niches.
Start with the structural dependency or failure mode, then show why decentralized architecture is necessary. Quantify uptime, concentration and jurisdiction risk, node and validator diversity, security, developer adoption, cost, and switching incentives. Explain the open-network economics and how the product becomes resilient critical infrastructure rather than a tokenized copy of a centralized service.
Developer teams building open and robust internet architecture, infrastructure with no central kill switch, products that turn decentralization into measurable resilience, technically mature networks tested under adversarial conditions, and protocols capable of serving governments, enterprises, and consumers beyond crypto trading.
No personal pass list is public. His published arguments imply weaker fit for speculative tokens without infrastructure utility, centralized products marketed as sovereign merely because of geography, systems with a single operator or jurisdictional choke point, and decentralized technology that cannot demonstrate reliability or practical adoption.
Assess operator concentration, geography, jurisdiction, fault isolation, vendor diversity, upgrade control, and whether the system keeps operating when components or institutions fail.
Map the communications, custody, computation, identity, settlement, and machine layers; identify each centralized choke point; and test the decentralized replacement's maturity and interoperability.
Favor infrastructure that has demonstrated uptime, security, and useful operation through outages, attacks, censorship, regulation, or geopolitical shocks rather than relying on architectural claims alone.
Digital sovereignty depends on resilient architecture—distributed control, fault isolation, open rules, and no single jurisdiction or kill switch—not merely replacing foreign centralized vendors with European ones.
Privacy-preserving network infrastructure is a foundational layer for a more open, decentralized, and robust internet architecture.
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