Exactly as @Midwest Trucker said, they ask for them, Great West also asked for them. In my case I hoped it would help as I don’t run the northeast. The DOT also asked for them in new entrant audit. Nothing there to hide.
Progressive deals with a lot of various carriers, depending on the region, different regions, different rules it seems. I filed for my MC number this past Spring, already had my DOT# though as a private carrier since 2011. Two insurers to choose from, went with Progressive, was asked what radius do you want, 100-200-300-500-unlimited. Went with the 300 as I run a regional day cab interstate, but am home every night, 500 radius would have been an additional $700 a year, didn't even ask about unlimited. I have no problem providing them my IFTA miles, might even lower my rate more, I dunno?
I'm with Great West. They've never asked for my IFTA returns nor were they part of my NESA. I must be living in some alternative universe than you guys. I have nothing to hide but my taxes are between my state department and me only. I have blinds over my windows too but I have nothing to hide there either.
I have no problem giving state mileage from my returns but I'm not giving out my returns to anyone. If nobody has anything to hide; why not use that little snitch box for them? Or let them track your every move with your ELD? It's all intrusive. I know I'm the minority here but that's just how I am. If they ever stop the ELD exemption for pre-2k trucks I'd quit too.
I am with Great West as well. I give them the miles ran per state since they request it. Not too big of a deal. I’m surprised they don’t ask.
I can freely share my state mileage (if they were to ask for it) I have no problem with that but I won't give out my filings/returns.