Strat 4's only "duped" gear was from the dress price change which someone bought 9999999999 and sold them all for crazy money.
Their might have been other stuff, but that's so fucking long ago who cares.
Wonder if it'd be fun to do the chart again for strat 6?
There was a ton of duped gear. And if you checked the renown, the recipients were fairly obvious.
As far as FCC goes, the only duped gear I was aware about came from my battle with Artyem. We both received duped gear, then Artyem gave me some of his gold from duped gear, I left FCC and started doing EXP battles. There are certainly other tactics that FCC used that were questionable, and some were hilarious. But I honestly don't believe they used any duped gear.
Oh, and the lions share of Artyem's gear that did end up getting duped was from him attacking a random who has tons of free dresses. Sometime between that guy buying the dresses and actually getting attacked, the devs changed the Strat price from free to something, which Artyem then sold for millions.
I'm not staying any of this to call people out, but there were for a fact, tons of duped gear and some factions didn't report the bug or ever admit to getting it. In fairness, the duped were all related to the battles happening on patch days, and weren't planned or purposely recreated.