Asset

Assets are kinds of objects of the world that have identities.

Prototype

{
    "wikidataQ": ".."
}

Note I: while registry of concepts does exist (e.g., wikidata.org), the registry of concept instances does not yet exist. Every country keeps a record of their cars, and certain other assets, and many web shops keep instances of schema.org schemas. There are no registry of unique ids for other types of assets. However, such registry could be created.

Note II: a WikiData expert mentioned, that WikiData is intended for concept instances, so, for example “Mona Lisa (Q12418)”, however it is obvious, that WikiData guidelines are to accept only items of prominence, therefore, concept-level things, rather than instance-level things, e.g. you are not supposed to register your car on WikiData.