Securities registered in the name of or assigned to a board, committee or other body authorized to act as a unit for any public or private trust estate may be assigned for any authorized transaction by anyone authorized to act in behalf of such body. Except as otherwise provided in this section, the assignments must be supported by a copy of a resolution adopted by the body, properly certified under its seal, or, if none, sworn to by a member of the body having access to its records. (Form PD 2495 may be used.) If the person assigning is designated in the resolution by title only, his incumbency must be duly certified by another member of the body. (Form PD 2446 may be used.) If the fiduciaries of any trust estate are empowered to act as a unit, although not designated as a board, committee or other body, securities registered in their names or assigned to them as such, or in their titles without their names, may be assigned by anyone authorized by the group to act in its behalf. Such assignments may be supported by a sworn copy of a resolution adopted by the group in accordance with the terms of the trust instrument, and proof of their authority to act as a unit may be required. As an alternative, assignments by all the fiduciaries, supported by proof of their incumbency, if not named on the securities, will be accepted.