From Wikipedia, Ruger MK II:
"Prior to Bill Ruger's partnership with Sturm, he had successfully duplicated two Baby Nambu pistols[1] while working in his garage, from a U.S. Marine's captured Nambu, shortly after World War II. Although deciding against marketing the Baby Nambu Pistols, Ruger did incorporate the Nambu style rear cocking device and modified the Nambu's silhouette, plus he added a 4.75 in (12.1 cm) lightweight barrel with fixed sights."
В смысле, Ругер сам сей факт признаёт.