Anyone can create nanopublications. Technically, only a user identifier and an RSA key pair are needed. In practice, when using a tool like Nanodash, you don't have to deal with keys yourself — it generates and manages them on your behalf, and you simply sign in. Nanodash currently requires an ORCID, while the nanopublication format itself accepts any persistent user identifier; using ORCID is strongly recommended in any case, as it makes attribution interoperable across the scholarly ecosystem. If you publish locally (for example via the nanopub command-line tools), you do need to generate and manage your own key pair.