How are Tax liens investments being taxed?

[George P.]

How are tax liens investments being taxed? I am yet to speak with an accountant thus ask the question here to get an idea.

I have bought the tax liens past summer. Most of them were redeemed within the first couple of months. On the rest I am hiring an attorney to proceed with the foreclosure.
Anticipating they will get redeemed before the summer of next year (holding period is less than a year), am I going to pay a regular income tax rate on the collected interest?
I understand the tax liens are passive investments in nature, but I am not sure if the 12-months holding period applies to them.