[littlestymaar]

From the article:

> Microsoft owes the Internal Revenue Service (IRS) $28.9 billion in back taxes, not including penalties and interest

[blitzar]

My bad first scan read (probably wrong now I look at it) was;

The IRS says Microsoft owes an additional $28.9 billion -- in tax for 2004 to 2013 plus penalties and interest

For an SEC filing they really should be declaring the actual value of their liability - the interest on the bill is going to be $10bn+

[cma]

There was close to a zero interest rate during all that time, or does IRS use something way above normal for their rate?

[blitzar]

Generally, in the case of a corporation, the underpayment rate is the federal short-term rate plus 3 percentage points and the overpayment rate is the federal short-term rate plus 2 percentage points. The rate for large corporate underpayments is the federal short-term rate plus 5 percentage points.

https://www.irs.gov/newsroom/interest-rates-increase-for-the...

[nkozyra]

Back taxes have a baseline rate that grows at certain increments of lateness but is ultimately capped. I don't think it's in any way tied to the base or prime rate.

[littlestymaar]

Based on what happens in my country, it could be both penalty + some interest rates based on the reference rate (which definitely haven't been zero for the past two years btw) but not equal to it.