以下のUSPTOのサイトにPOAの署名権限についての記載があります。米国では”authorized to act”を有する者が署名す ることができ、
“authorized to act”を有する者には、肩書から明らかに”authorized to act”を有することが認定される者や、取締役会の決議で権限が付与された者などが含まれます。
guid_aia-poa.pdf : https://www.uspto.gov/sites/default/files/forms/guid_aia-poa.pdf
The form must be signed by the named assignee or, where the assignee is a juristic entity, by someone who is
authorized to act on behalf of the assignee. Someone who is “authorized to act” would be an officer who
has a title that carries apparent authority or someone who have been given such
authority by, for example, a corporate resolution from a board of directors.
325-Establishing Right of Assignee To Take Action in Application Filed On or After September 16, 2012 : https://www.uspto.gov/web/offices/pac/mpep/s325.html
(A) The submission may be signed by a person in the organization having apparent authority to sign on behalf of the organization. 37 CFR 3.73(d)(2). An officer (chief executive officer, president, vice-president, secretary, or treasurer) is presumed to have authority to sign on behalf of the organization. The signature of the chairman of the board of directors is acceptable, but not the signature of an individual director. Modifications of these basic titles are acceptable, such as vice-president for sales, executive vice-president, assistant treasurer, vice-chairman of the board of directors. In foreign countries, a person who holds the title “Manager” or “Director” is normally an officer and is presumed to have the authority to sign on behalf of the organization.
以上の規定を考慮すると、取締役会において知財部長に署名権限を付与する旨を決議し、”Manager in IP Division”などの肩書で署名をすれば大丈夫です。