OK, I spent some time looking and according to the latest survey I could find (from 2014, http://mepag.nasa.gov/reports/Rummel_et_al_Astrobiology_14-SR-SAG2.pdf

OK, I spent some time looking and according to the latest survey I could find (from 2014, http://mepag.nasa.gov/reports/Rummel_et_al_Astrobiology_14-SR-SAG2.pdf http://mepag.nasa.gov/reports/Rummel_et_al_Astrobiology_14-S...), here is the state of knowledge: [Sec. 6] "Strong interest exists among various countries and private industries to send humans to Mars, both for short-term exploration and long-term colonization." (and on for 3 dense pages). So, private ventures are part of their deliberations. [Sec. 8, end] "It will be impossible for all human-associated processes and operations to be conducted within entirely closed systems, so protocols need to be established so (1) human missions to Mars will not contaminate Special Regions nor be contaminated by materials (or possibly organisms) from them and (2) human activities on Mars will avoid converting Non-Special Regions to Special Regions and thus help control the spread of terrestrial microorganisms on Mars." * The basic strategy is to identify and avoid "Special Regions".