We inherited 25% of a house. 50% stayed with the (still living) father, and the other 25% went to a sibling. Do we need to claim home ownership?

[jtax]

Claim what? Did you sell the house? Who lived in the house?

[jtax]

If you are asking if the inheritance is income and needs to be reported on your federal 1040, the answer is no. Gifts are not income. https://www.law.cornell.edu/uscode/text/26/102

When the property is sold you will owe capital gains on the selling price - expenses of the sale - your  basis.

For gifts from living donors, your their basis when the gift was made. (Unless they were underwater.)

Their basis is the price they paid to buy the property plus any improvements made over the years.

[Hal_Al]

Q. Do we need to claim home ownership?

A. No.

You do not "claim" home ownership on your taxes.  TurboTax only asks that question to direct you to enter some potential itemized  deductions: mortgage interest and real estate taxes.  

If you  do not already itemize deductions, these are unlikely to benefit you even if you are paying 25% of those expenses.