From the old group :
https://groups.google.com/d/msg/inaturalist/-QJM52iQm10/-K2EZY8FBwAJ
So it is 100 km, and within 45 calendar days (anyyear +/- 45 days) so if you see something in March and the only prior iNat record was from the exact same gps but in September, it will not be considered as seen nearby
Please note
- there are clear bugs where it does not get it right, where something should qualify but is not reported as seen nearby, II have documented this several times and communicated it, I’ve never heard back on those bugs
- you should not consider something not reported as seen nearby as not a viable choice, both due to the 45 days criteria, but it may just be there are no iNat records from it yet, especially outside busy usage areas