Legal Boundaries of Blockchain Technologies : Smart Contracts as Self-Help?

As a consequence of the blockchain revolution, a key challenge of our times is to identify the legal boundaries of smart contracts and thus to develop conflict rules for divergences between state law and technology-based code. Even if smart contracts are technologically self-executing, they are not necessarily legally enforceable. Rather, they must satisfy a variety of legal and contract law requirements. Two different levels of such rules can be differentiated, namely rules of recognition and substantive restrictions. At both levels, it emerges that either the lawmaker can intervene and introduce new, specific rules, or the judiciary can develop rules on the basis of existing and more general legal standards. For example, at the European level the Unfair Terms Directive and (in future) the Directive on Contracts for the Supply of Digital Content limit the potential scope of smart contracts. At national level, the rules on self-help constitute a crucial legal boundary. At least some applications of blockchain technology will be subject to these rules, strictly limiting their admissibility. Under German law, for instance, a waiver of the relevant provisions is largely excluded. In the case of cross-border situations, the comparative divergence of self-help rules will create legal uncertainty and may hinder the use of smart contracts