Who has the "capacity to sign" Form W-8BEN or W-8BEN-E?
On Form W-8BEN-E, an authorized representative or officer of the entity signs and checks the box certifying capacity to sign for the entity on line 1. On Form W-8BEN, the individual signs; an agent signing for them checks the capacity box and attaches the power of attorney.
Form W-8BEN-E (entities) The form must be signed and dated by an authorized representative or officer of the beneficial owner, the participating payee (for section 6050W purposes), or the FFI account holder the form is given for. The signer must check the box certifying that they have the legal capacity to sign for the entity identified on line 1 that is the beneficial owner of the income (Instructions for Form W-8BEN-E, Part XXX). The instructions don't list which titles qualify: the signer certifies their own authority by checking the box.
Form W-8BEN (individuals) The beneficial owner or FFI account holder signs, or an agent with legal authority to act on the person's behalf. An agent signing for the beneficial owner should check the box indicating that the agent has capacity to sign for them (Instructions for Form W-8BEN, Part III).
Signing through an agent On either form, an agent acting under a duly authorized power of attorney must attach the power of attorney, or a copy, in proper form and specifically authorizing the agent to make, execute and present the form. Form 2848 can be used. The agent, as well as the beneficial owner, payee or account holder, may be liable for the penalties for an erroneous, false or fraudulent form.
What signing commits the entity to By signing Form W-8BEN-E, the authorized representative, officer or agent agrees to provide a new form within 30 days after a change in circumstances that makes the form incorrect.
Electronic signatures A withholding agent may accept either form with an electronic signature. It must show that a person authorized to sign did so: for example, the signer's name in the signature block, a time and date stamp, and a statement that the form was electronically signed. Typing a name into the signature line is not an electronic signature. A withholding agent may also rely on an electronically signed form if the signer provides the additional information it asks for to show an authorized person signed (Treas. Reg. § 1.1441-1(e)(4)(i)(B); Instructions for the Requester of Forms W-8).