The EU regulation at:

http://data.consilium.europa.eu/doc/document/ST-5419-2016-INIT/en/pdf

On its "Article 17" on page 141, details the "Right to Erasure" for EU citizens. It requires that data controllers remove data from EU citizens on request. How decentralized p2p networks are supposed to comply with this? There is no way to force deletion or erasure of data on networks like that. Specially if we're talking about blockchain-based networks where data is being added to the chain.

Can some lawyer chime in? This a big issue for adoption of decentralized protocols by a larger audience.