Anonymized MLAT results on local dump1090-fa

I learned that forwarded MLAT results contain anonymized flights. But yesterday and today I noticed anonymized MLAT results on my local dump1090-fa. Any ideas?

It’s not about forwarding.

Some MLAT results are just anonymized, see this announcement:

FlightAware MLAT Network Announcement

I see. So I misunderstood that announcement.

The anonymized MLAT results were introduced because some people were aggregating/forwarding MLAT results.

But as the MLAT data isn’t under control of FA anymore as soon as it leaves their server, the anonymization obviously needs to occur there.
So it wouldn’t be possible to “detect” that forwarding and anonymize only then.