Please provide detailed information about whether the second owner’s PAN card can be used to avail House Rent Allowance (HRA) benefits in the context of a jointly-owned flat.

Ans: Yes you can claim both

Ans: At the end its the same as either you take benefit of 80C and interest or HRA , it'll be either or in this case.

Ans: No, you cannot claim HRA (House Rent Allowance) if you own the property where your parents live and you pay them rent for another flat in the same building.

Here's why:

HRA benefit is for rented accommodation: The purpose of HRA is to provide tax relief for salaried individuals who pay rent for a place they live in, but don't own.
Ownership of the property disqualifies you: Since you own the property where your parents reside, even if you're paying rent for a different flat, you wouldn't be eligible for HRA.
Here are some important points to remember about claiming HRA:

The property you pay rent for should be owned by someone else, not yourself or your relatives.
You must have valid rent receipts as proof of payment.
The rent amount paid should be at least a certain percentage of your salary (as per Income Tax Act).
Alternatives to consider:

If you're looking to save tax, you might explore other options available under Section 80C of the Income Tax Act, like investments in Public Provident Fund (PPF), Employee Provident Fund (EPF), or Equity Linked Savings Schemes (ELSS).
It's always advisable to consult a tax advisor for personalized guidance based on your specific situation. They can help you understand the latest tax regulations and recommend the most suitable tax-saving options for you.