All communications between a lawyer and a client are automatically privileged (confidential). The privilege extends to all members of the attorney’s law firm, including staff members. Therefore, if a client’s spouse, friend, relative, or the like calls an attorney and requests a status report on a case, or seeks some other information about a prospective, pending, or concluded matter, the attorney can not provide the requested information and can not even acknowledge whether or not the firm even represents that client. 

However, after a patent has issued, it is public information that the inventor is a client of the firm. Still, we can not release any information about the client or any inventions for which a patent may be pending. The attorney-client privilege belongs to the client so the client can waive it but the attorney can not. An inventor need not obtain the signature of a patent attorney on a Non Disclosure Agreement prior to disclosing the invention because, again, the privilege is automatic and no written NDA is necessary.