Cool, this one has SOA down to DC. That's rare nowadays 
Becareful, the SOA shown that its has DC chart, it is
not realistic temperature as the TC at 25C, especially its not a linear mosfet.
Once crossed the 25C, you just can not interpolated that DC chart, as sometimes the max current will be reduced significantly, especially for non linear mosfets.
An example of a proper and true linear mosfet FBSOA, watch the yellow highlighted areas and compare both charts.
-securing-sot-227-mosfet-to-heatsink-base-mosfet_s-fbsoa/?action=dlattach;attach=225611;image)