While investigating the spam campaign of 2015, I stumbled upon a wallet which I believed to be the QuadrigaCX exchange but I wasn't able to confirm my theory. Years later, it appeared that these weird transactions were G.Cotten robbing his own exchange.

For the sake of clarity: By "weird transactions" I don't mean the spam transactions but a set of transactions sending money directly from Quadriga's cold wallet to a mixer. 😅