Is the DOS clause actually spelled out in the mortgage or just implied because it's not assumable?

[Matthew Hall]

The mortgage I'm looking at says nothing about a DOS clause but does say it does not have a "Demand Feature," which apparently allows the lender to call the loan due for any reason. It does however have a box checked that states that the loan is not assumable. So given that, is a DOS automatically implied as the penalty or trigger for doing a sub2 or similar deal?