TD要求Foreign tax identifying number? - 理財

今天收到一份TD 的e-mail

A new regulation requires TD Ameritrade to collect your foreign tax
identifying number before January 1, 2018. Our records as of September 6,
2017, indicate that we don't have this number on file for your account. To
avoid backup withholding and comply with U.S. tax regulations, please send us
a completed and signed Foreign Tax ID Number Form from each account owner.

We encourage you to send us this form as early as possible. To allow time for
processing, we'll need to receive it by December 8, 2017.

If you have a foreign tax identifying number, you may provide this in the Tax
Identification Number section of the form. If you are not legally required to
obtain a tax identification number in your jurisdiction of tax residence, you
may complete the Reasonable Explanation section. However, if your country has
an Intergovernmental Agreement (IGA) with the United States and requires a
foreign tax identifying number, TD Ameritrade cannot accept the Reasonable
Explanation Form in lieu of that number.

How to Send Us Your Form(s)

You may send your form(s) to us electronically, fax it, or mail it to us.
To submit the completed and signed form(s) electronically through our secure
Message Center, scan it, along with any other material you're sending, then
attach the scanned document(s) when you reply to this message.

If you'd prefer, you can fax us your form(s) at 866-468-6268.

Or you can mail it to us, at:

TD Ameritrade
200 South 108th Avenue
Omaha, NE 68154-2631
United States of America (if you're mailing this material from outside the
United States)

請問是甚麼意思呢？我該怎麼做呢？

麻煩版大們解惑，謝謝

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