Three codes could be found in the ANOMALY FOOTPRINTS AND PHASES post on the Investigate Ingress blog.
[1] 4frq6gatiuon3x8mjy
[2] xewnvemlbncldvebvxwnwxdeebnvnxc
[3] a8y29wkhe2janigm
Code #1
Observations
18 characters with the right amount of numbers for a valid passcode
Code #2
Observations
All letters without real specific range. In the end you’ll need 0 & 1
Code #3
Observations
16 characters with the right amount of numbers for a valid passcode. This time with a real twist