Yes, 0.1 mm diameter enameled copper wire.
Chasing GPL violations sounds like a fun hobby :)
Pre-OpenWRT days I was maintained a Linux distro ISL3893 that ended up in court in Germany, the first GPL enforcement:
"17 apr 2004 — GPL testing in court by the Netfilter/Iptables team, due to refuse to give source code of the Sitecom WL-122 (isl3893 based!). In the same time, some source code has appeared on the webserver of Sitecom."