Basically, turkey did not have to aqquire license from HK, the same way the HK did not have to get a license from Colt, although they are exactly the same in when you look at them(which makes both of them a Colt M4 look-alike) . The Turkish version is made of a new metal, known as Inter Alia, which is more resistant to elements(Turkish forces in the mountains will be happy to here this i suppose).
Inter Alia is also lighter and does not expand as quick as other metals when heated, which is good for long firefights i would guess...
Although HK have given them the OK to produce the rifle without any legal complications(they wont sue, for external appearance similarities)...Anyone here who has any legal knowledge would know that if it were licensed it would use the name HK416, not Mehmetchik-1..MKE and HK have been long time partners and it would take an immense amount of bad happenings to seperate the duo...HK even gave MKE the design prints for the HK416-417.
But MKE gave something back in return, a new type of bullet, not different caliber but bullet, apparently, when it discharges, the gunpowder burns from the front to the back, thus, leaving ver little dirt in the barrel, an innovation in bullet design in HK's opinion, but not in mine, it is more of an upgrade than an innovation in my opinion