Ward J.A. decided that documents prepared to support potential future litigation were protected by the work product doctrine. Id. at 16. For example, documents that disclosed Inpro`s litigation and licensing strategies with revenue information were protected as a working product. Id. Ward J. also found that, although these documents were passed on to third parties, there was no waiver of the contract of the working product, the documents being provided subject to confidentiality agreements. The court ultimately found that such disclosure “did not significantly increase the likelihood that an adversary would take possession of the materials. Id. at 17. Legal systems differ greatly in their treatment of privileges of common interest.
In a jurisdiction that recognizes the privilege of common interest, the parties should be aware of the common pitfalls, in particular the absence of a finding of common interest. In order to extend solicitor-client privilege to non-interested parties, the parties should execute a written agreement at the time of disclosure in order to have a common legal interest in all information exchanged. Although no written agreement is required, it can be difficult to prove that an oral agreement has been reached and that it has been binding. In addition, the common interest agreement should clearly define the common legal interest. The doctrine of common interest provides that a communication that would otherwise be considered privileged may remain privileged vis-à-vis third parties if two or more separate companies that share a legal, real or strategic interest exchange information between them and their respective lawyers.  In general, the presence of a third party destroys the privileged nature of communication between the lawyer and the client.  But according to the doctrine of the common interest, a privileged communication must not be deprived of its privileged status because of the presence of a third party.  When certain conditions are met, the doctrine allows parties with common legal interests to freely and collectively share reciprocal resources without fear of privilege. The use of the doctrine of common interest for the exchange of information promotes cooperation between similar parties, promotes cost-sharing as a whole, and can help lawyers and clients deal more effectively with real or threatened claims or defences. A lack of judicial instruction, which defines the more nuanced limits of teaching, can increase sleep in this area. For example, what is a “legal interest” as opposed to a commercial interest? How does a jurisdiction determine whether a legal interest is sufficiently “common” between the parties? Can communication between clients and clients be protected by the doctrine of the common interest in the presence of a lawyer, without the lawyer being actively counseled or involved? The jurisprudence on the doctrine of the common interest has not been able to keep up with the evolution of the way lawyers and their clients communicate.