A lawyer may be adverse to a former client, but not in the same matter in which she represented the client, or in one which is “substantially related” to the representation of the former client. Generally, this requires determining whether it is reasonably likely that in the representation, the lawyer likely learned confidential information that likely can be used against the former client now.
One part of that analysis can require determining what information “counts.” This varies by jurisdiction: some, for example, do not include information known to the new client, or “playbook” information (e.g., how a client approaches IPRs), and so on. And, some do not count information if it has become “generally known.”
In the context of prosecution, for example, does the fact that an application has published mean it is “generally known” and so no longer counts?
The ABA just released an opinion on this point, ABA Formal Eth. Op. 479 (Dec. 15, 2017), here. The abstract explains:
The “generally known” exception to the duty of former – client confidentiality is limited. It applies (1) only to the use, and not the disclosure or revelation, of former – client information; and (2) only if the information has become (a) widely recognized by members of the public in the relevant geographic area; or (b) widely recognized in the former client’s industry, profession, or trade. Information is not “generally known” simply because it has been discussed in open court, or is available in court records, in libraries, or in other public repositories of information.