Board Thread:General Discussion/@comment-27031996-20160808063610/@comment-24815383-20160809111721

It focuses mostly on the Avengers, but as you can see, its subtitle is "Framework for the Registration and Employment of ENHANCED INDIVIDUALS". These super-enhancement stuff is still an extremely rare phenomenon around the world, and they know they can't control super-criminals, so they aim at controlling heroes, which in the MCU are mostly covered by the Avengers. Spider-man was still very new, nothing more than a vigilante, the story of Ant-Man not older than a year, so they focused on the well-known, proven, active and powerful enhanced individuals who worked without governmental control, our beloved avengers. Even though the existence of SHIELD is publically unknown, the American president and many bigwigs know that they exist and act in the shadows. Both the ATCU, focusing on "advanced threats" and SHIELD  are very close to the enhanced world, so it's not a surprise that they should first register their enhance agents, before they can deploy them.

So, in a nuttshell, based on the data from the coversheet of the Accords and AoS it's focusing on all enhanced who wants to get rid of crime with the usage   of their powers.