The new ARRI Alexa 35 is already certified for Netflix 4K productions - anything but surprising, after all, the camera was developed among other things to close precisely this gap. It is the first Alexa with a Super35 sensor to make the list, thanks to the new ALEV 4 CMOS sensor with its 4.6K resolution. The other three cameras recommended by Netflix have a larger sensor (LF).
Netflix-certified: ARRI Alexa 35
Both ARRI RAW and Apple ProRes recording are allowed, but the latter only with 4444 / 4444XQ compression. The following sensor modes are available for selection depending on project requirements (spherical / anamorphic, target aspect ratio, etc.)
4.6K 3:2 Open Gate
4.6K 16:9
4K 16:9
4K 2:1
3.3K 6:5
3K 1:1
As always, more detailed information and notes can be found in the corresponding 
Camera Production Guide.
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