When do I need to make a modification to my rental real estate, royalties, K-1 or capital gain amounts?

There are a number of circumstances where you may need to modify the amounts for your business, rental real estate, royalties, K-1 or capital gains. This includes if you participated in an activity involving research or experimentation or in some cases when you recharacterize passive rental income. Please see the Form 8960 instructions  for more information.