I also just received the same letter for the 2016 tax year.
Yes the information at https://www.colorado.gov/pacific/sites/default/files/Income15.pdf
states purchased after May 1994 and before June 2009.
However, the 2016 tax filing instructions shown here: https://cotaxaide.org/docs/2016%20CO%20DR%200104AD%20Instructions.pdf
make no mention of the June 2009 requirement.
Line 5 Colorado Source Capital Gain
Subtraction
You might be eligible to subtract the income you earned
from a Colorado-source capital gain. We recommend that
you read publication FYI Income 15 if this applies to you.
The amount of this subtraction is limited to $100,000 and
qualifies if the capital gain was:
• Earned from the sale of real or tangible personal
property that was located in Colorado at the time
of the sale transaction; and
• Included on your federal income tax return and is
calculated as part of your federal taxable income;
and
• Acquired on or after May 9, 1994 and was owned
continuously for five years prior to the sale
transaction date.
I plan to use the state's instructions for filing an appeal.
