Hi Moni.
Checked it out for you. The (new) tax treaty for Spain is the one from 2013 that replaces some articles from the treaty of 1990. Here is the IRS link to the respective PDF: https://home.treasury.gov/system/files/131/Treaty-Spain-Protocol-1-14-2013.pdf
In Article 12 that handles Royalties, it says:
"Article VI
Article 12 (Royalties) of the Convention shall be deleted and replaced by the
following:"
"1. Royalties arising in a Contracting State and beneficially owned by a
resident of the other Contracting State shall be taxable only in that other State."
and
"2. The term "royalties" as used in this Article means payments of any kind
received as a consideration for the use of, or the right to use, any copyright of
literary, artistic, scientific or other work (including cinematographic films, and
films and recordings for radio or television broadcasting), any patent, trademark,
design or model, plan, secret formula or process, or for information concerning
industrial, commercial or scientific experience."
So, in your case, the correct Article and Paragraph is 12(1) and the Royalty Rate is 0%.
For the rest, see my related thread: https://community.zazzle.com/t5/share-your-tips-tricks/w-8ben-links-to-irs-documents-and-tips-for-fo...
This should solve your issue. Feel free to head back to me if it doesn't work out.
Good luck and greetings from Italy.
