By Nikolai Gorshkov BBC Moscow correspondent

A two-year legal dispute between Russian companies for the copyright of the world-famous Kalashnikov assault rifle has been won by its original producer in the Urals.

The AK-47 is a weapon of choice for rebels and gangsters the world over... a staggering 100 million AKs have been produced so far - enough to arm all the armies of the world

Kalashnikovs - or AK-47s - are made in 19 countries, of which only a few have been paying royalties.

Those not paying have claimed there was not a sole patent holder.

The AK-47 is a weapon of choice for rebels and gangsters the world over.

AK is very simple to make and easy to use

It was designed by a retired Red Army officer Mikhail Kalashnikov at the end of the World War II and despite numerous modifications remains essentially the same.

It is simple to make and to use - making it easy to copy for dozens of arms manufacturers around the world.

A staggering 100 million AKs have been produced so far - enough to arm all the armies of the world.

The AK has made it into 55 national armies, and onto six national flags.

Soviet bloc countries acquired it officially and virtually free of charge, others took advantage of the fact that the USSR was not party to international copyright agreements.

Loopholes

This past self-imposed isolation is now haunting Russian producers of anything from vodka to weapons.

Mikhail Kalashnikov first designed the rifle at the end of WWII

They have been fighting legal battles to get back their brand names lifted by unscrupulous rivals both at home and abroad.

But there are loopholes in the recently adopted Russian copyright law that allow domestic manufacturers to pirate foreign goods.

Music CDs and computer software are copied on an industrial scale and sold across Russia for a fraction of what they cost in the West.

So, Russia's complaints about copyright abuse are usually met with suggestions to put its own house in order.

There are several long-running disputes between the Russian manufacturers.

Now that the one over the Kalashnikov rifle appears to have been resolved, its maker is planning to sue foreign manufacturers to the tune of $18 million in unpaid royalties.

But many insist their products have only a passing likeness to the famous assault rifle.

It looks like the copyright war will be the toughest battle the Kalashnikov has ever had to fight.