Dear Miami Landlord:
I am an attorney licensed to practice law in New York. I do not practice law in Florida.
Forms for a Florida three day notice, as well as guides to landlord and tenant legal issues may be found here:
If you meant that you do not know the names of other persons unknown to you who may be residing in the rented premises, along with the tenant, the normal method to name persons unknown, whether in possession or may be in possession is to name those persons as "John Doe" and "Jane Doe."
Whether you need to name fictitious person who may also be in possession of the premises when you make your three day notice is something you have to discover on your own or by speaking with a local attorney.
You should know the names of your tenants, and the model forms only seem to require that the rent demand be made on the "tenant" .
Please review the statute here:
and when filing the Complaint for possession here:
Read more at:
It may be a good idea to see an attorney, as there are lawyers in your area who specialize in landlord proceedings. Better to be sure that the case was done right than be your own experiment.
The answer provided to you is in the nature of general information. The general proposition being that you should try to avoid a bad outcome if you can.
There exist Florida caselaw which suggest that if a Landlord does have knowledge of individuals living on the property as tenants, despite not being named on the lease agreement, they are required to be named as unknown defendants. Failure to do so runs the risk that such tenants moving to dismiss the action for failure to name an indispensable party. It is recommended that you name at least one "John Doe as Tenant in Possession" or "All other individuals in possession" to avoid any possible surprises.