While blockchain technology can promote competition in many industries, it also has the potential to be used in a way that risks non-compliance with competition law. Participating users of a blockchain, particularly a permissioned consortium blockchain, may be competitors operating within the same market. Co-operative behaviour between such entities must therefore avoid giving rise to conduct which may be considered anti-competitive.

For example, when transaction information is visible to any nodes operating on a blockchain, the exchange of sensitive information (e.g., pricing information) between competitors may cause concerns due to the risk of price fixing or of facilitating collusion. In some cases, an additional layer of cryptographic protection may need to be implemented to protect sensitive or strategic information. That being said, the transparent nature of a blockchain can also be an opportunity to foster efficiency, and the mere fact that transaction data is available to participants does not automatically suggest that competition laws are infringed.

In the context of permissioned blockchains, the rules or criteria for participation must be reasonable and objective, as rules which exclude competitors in a discriminatory manner may breach competition law. Similarly, agreements to set common technical standards on a blockchain may be an important element of ensuring the smooth operation of a platform, but access to such standards should not result in unnecessary restrictions to participation. A particular challenge for blockchain users is to ensure competition law compliance globally due to the borderless nature of the technology.

On the flip side, blockchain technology also presents opportunities for enhancing competition law compliance. For instance, an openly accessible ledger that improves the availability and reliability of transaction information may promote competition by reducing information asymmetry.