Here is The Story
Ever picked up a .243 case, a 308, a 7mm Rmington Mag. Even though the .243 case may be made by Remington, it says "Remington, .243 Winchester".
Same for the others. The actual originator of the chambering gets the name on the case head as well as the manufacturer. Pick up a 7mm Mag case at the range. Heck, it could be manufactured by anybody, but it still has "Remington 7mmMagnum" on the head.
Norma is the manufacturer that standardized the 6BR at what we know now, the length of 1.560. Remember, the originol Remington was 1.500, (or there abouts).
When Lapua started manufacturing 6BR Brass, they used the Norma as their standard, so they have to put 6BR Norma on the headstamp, along with Lapua.
But, after saying all of that, there is a major difference in a 6BR case manufactured by Lapua and one by Norma. The Lapua case will be as much as .002 larger at the web. I guess that isn't a big enough difference to cancel out the royaties.
But it can present a problem if a shooter has a Rifle chambered for the originol Norma Specs, or even the originol Remington. Lapua cases would not go in.
Most reamers made now are ground to use Lapua Brass........jackie