Where the interest claimed in a caveat is based upon an easement, and the easement is not a statutory easement (as detailed in section 111 of The Real Property Act) the caveat must contain the legal description of both the dominant and servient lands.
Caveats giving notice of easements can only be registered by the current owner of the dominant lands. Where an agreement contains reciprocal easements (i.e. it creates easement rights in favour of both parcels of land), for each owner to be protected, each of them must register a separate caveat giving notice of the easement in their favour. A joint easement cannot be registered by the parties.
Section 111 caveats do not require dominant lands. These caveats are typically registered by the Crown, a municipality, Hydro, Bell MTS, or a similar agency, for the supply of some service – water, electricity, etc. For a discussion of these instruments, see Statutory Easements in Easements.