Surprisingly, similar markings involving trisula and katars were recently discussed ("Help with these Marks" by Alex June 20,2007). The marks on this tulwar seem very familiar, and if I can recall, identical to others I have seen. Whether this means there are a number of swords from a certain maker or arsenal I cannot say, but it suggests that either the same sword is getting around a lot!
or as I have noted, there are a number remarkably similar.
Excellent cite from Elgood on the trisula stamp Jens!! Now again we return to the katar as discussed in Egerton (in the thread noted above), and again wonder if the siginficance could be as suggested.
Best regards,
Jim