The bill being introduced is concerned with the state of Minnesota's rules on estate taxation. It aims to update and remove outdated elements and introduce a provision that allows for the transferability of the estate tax exemption between spouses, which isn’t specified in the text you provided but is generally what "portability" refers to in estate tax context.

Moreover, the bill revises the requirements for when an estate tax return needs to be filed in Minnesota. Specifically, it states that a return is necessary if either a federal estate tax return must be submitted or the total of the decedent’s federal gross estate and taxable gifts within three years of their death exceeds certain specified amounts. These amounts increase over time: starting at $1.2 million for deaths in 2014 up to $3 million for 2020 and thereafter. This change adjusts the thresholds over time to reflect different values of estates and potentially other factors like inflation.

The bill includes technical details specifying how the tax return should be submitted and signed by the estate's personal representative.