Colt has held a US
trademark on the word "M4"
Many manufacturers produce firearms that come very close in terms of
appearance to a military M4, sometimes colloquially referred to as an
"M4gery"
,a
portmanteauof "M4" and "forgery"). Colt has maintained that it retains sole rights
to the M4 name and design. Other manufacturers had long maintained that
Colt had been overstating their rights — "M4" has now become more of a
generic term for a shortened M16/AR-15. In April 2004, Colt filed a
lawsuit against
Heckler & Koch and
Bushmaster Firearms, claiming acts of
trademark infringement,
trade dress infringement,
trademark dilution, false designation of origin,
false advertising,
patent infringement,
unfair competition, and deceptive trade practices. Heckler & Koch later settled out of court, changing one product's name from "HK M4" to
"HK416". However, on 8 December 2005, a District court judge in
Maine granted a
summary judgmentin favor of Bushmaster Firearms, dismissing all of Colt's claims except
for false advertising. On the latter claim, Colt could not recover
monetary damages. More importantly, the court ruled that "M4" was now a
generic name, and that Colt's trademark should be revoked.