It's not unusual at to try and connect Saginaw S'G' and Irwin Pedersen in online gun auctions, mainly for greed purposes though. Most of us know the history betwen the two. But if someone can "claim" the receiver was made by IP (whether true or not) then they will gladly hail it as part of the limted number of IP receivers out there. In my book, an IP gun or receiver marked IP is just that and should be sold as that. A Saginaw S'G' marked receiver or gun is just that and should be marketed as that. That's probably too novel of an approach though in today's crazy M1carbine market. BTW, there was definitely some overrun in serial numbers between Saginaw SG and Saginaw Grand Rapids; this particular carbine appears to be one.