This is a very interesting article. The attorney-client privilege is an important confidentiality rule that protects certain communications between a client and the lawyer/law-firm. The attorney-client privilege is an important privilege because it encourages clients to be candid with their attorney.
The ABA adopted Resolution 103, which provides that the attorney-client privilege extends to communications between a law firm and in-house counsel for the purpose of facilitating legal services. The resolution provides that these communications are protected to the same extent between the lawyer/law-firm and personnel of a corporation or other entity.
The ABA explains,
The measure stems from the increasing complexity of regulation, rules of professional conduct and greater disclosure obligations under legislation such as the Sarbanes-Oxley Act.