Sega Genesis Cartridge (missing copper contacts)

[bikingjahuty]

I was wondering if anyone could fill me in why some Sega Genesis games are missing some of the copper contact strips on the bottom of Sega Genesis cartridges? I found another copy of Contra Hard Corps over the weekend and while comparing it to my original copy, I noticed the one I picked up is missing about 10 of its copper contact strips on the front side of board, while the other copy has all of them. I have several other Sega Genesis games that are missing some of these strips and none of them seem to effect the game. I have read that this is the way certain game boards were made, just curious as to why.

[ffxik]

My best guess would be country and facility of manufacture differences.   

[tripredacus]

There is no definitive answer, only guesses. In some cases, PAL SMS games do not work in certain regions due to the pinouts being different. Took me a while but I found these other discussions on the subject:
http://segasaturngroup.proboards.com/thread/5584
http://www.sega-16.com/forum/showthread.php?21404-Game-differences

[archer9234]

It saves on cost. They took out contacts that aren't used. The game doesn't use them. NES carts did this a lot. The games were originally designed with 60 pins. So the extra 12 the NES added did nothing. So you'll see the 6 pin gap on a lot of later made games.