A billionaire buys a painting for $100,000, holds onto it for five years, then has it appraised at $10 million before donating it to a museum. The potential tax

A billionaire buys a painting for $100,000, holds onto it for five years, then has it appraised at $10 million before donating it to a museum. The potential tax deduction may be based on the artwork’s qualified fair-market value rather than its original purchase price, subject to strict IRS rules an…