The CX-9 was redesigned for 2016. The 2016 CX-9 adds a tether anchor to the 3P (but sadly not for 3D…). When installing a forward-facing car seat in 3P, Mazda instructs to route the tether around the 3rd row head restraint – we recommend routing it so it goes around the side that is closest to the door where the child is sitting – as this routing path will allow it to be more effective in a side impact crash than if it were routed on the side closer to the center of the car.
While in the earlier versions of the CX-9 all the seat belt buckles were flexible – they are now all rigid, which severely limits the use of 2C for car seats installed with a seat belt, and fitting 2 seats side-by-side in 2D & 2C most notably.
The shoulder belt for 2C comes from the roof. Yes this is safe. See here for how to connect and use this type of seat belt.
Mazda states that the vehicle head restraint must be removed when installing any forward-facing car seat or high back booster (make sure to store it in your house so you don’t lose it – but also so it doesn’t fly around the car and hit someone in a crash).
A key new feature for 2016 is the introduction of a car seat safe tilt for 2P in order to access the 3rd row.
Mazda states that the vehicle head restraint must be removed when installing any forward-facing car seat or high back booster (make sure to store it in your house so you don’t lose it – but also so it doesn’t fly around the car and hit someone in a crash).
The spacing between the innermost lower anchors is 19 inches – see here for more about this type of “center LATCH.” 
The shoulder belt for 2C comes from the roof. Yes this is safe. See here for how to connect and use this type of seat belt.
Within the 2007-2015 model year range, the only change made was that starting in 2012 the 3rd row head restraints went from being adjustable and removable, to ones that flip up/down and are not removable.
The spacing between the innermost lower anchors is 19 inches – see here for more about this type of “center LATCH.”
2013 Mazda CX-9
2014 Mazda CX-9
2014 Mazda CX-9 tether anchors
2011 Mazda CX-9 showing narrow center seat
2013 Mazda CX-9 – emily in 3rd row
