Forbes disagrees and quotes treas reg 1.163-1(b)
2. Who is listed as the borrower on the mortgage? In general, a taxpayer can only deduct interest on debt for which he is legally obligation. He cannot deduct interest he pays on a debt that isn’t his.
3. Who has legal title to the house? Treas. Reg. §1.163-1(b) provides an exception to the general rule found in #2. Pursuant to the regulations, even if you’re not directly liable on the mortgage, you can deduct any interest you pay on the debt as long as you are the legal owner of the house (e.g., a deed holder).
http://www.forbes.com/sites/anthonynitti/2014/12/30/five-traps-to-avoid-when-deducting-mortgage-inte...
Disclaimer: Not a tax professional. Information gathered from internet links. Anything dated in June 2019 was posted in prior years and is before the 2019 limits and changes.
