How to spot a fake GBA cartridge

Spotting bootlegs
Things to watch out for:
 * The cart label will be incorrect.
 * The cart will be a wrong color plastic.
 * Legit GBA carts grips fade into the plastic casing. Bootleg carts usually end abruptly.
 * Bootleg carts will not have the Pat.Pend or Made in Japan text imprinted.
 * Bootleg carts model number will be in the wrong font.
 * Bootleg carts will sometimes misspell Nintendo.
 * If you are purchasing your game on online sites such as eBay, it's probably a good idea to not buy from sellers located in Hong Kong or China.
 * Most of the time if you crack open the cartaigde of the game, It will have black putty (or something like that). Be aware that this rarely happens if it is a DS cartaigde.
 * On the inside of the chip the word "nintendo" was a circle around it should be printed as well as a series of numbers matching the game type and sometimes a year as well.
 * It is very common for the text on the cartilage itself to be indented in more if it is a bootleg.
 * The nintendo seal of approval may be missing or may be "blurry", meaning it was most likely printed on.
 * In Pokémon games the cartilage sticker may not be holographic if it is supposed to be holograpic.
 * Smaller more fine detials include things like dents on the inner chip as well as what you should see when you turn a translucent chip upside down.
 * On the right side on the front of the cartridge is an indentation, it is very unnoticeable at first but with the use of the light or running your finger over it you can usually spot it. It's usually some sort iof combination of letters and numbers, bootleg games don't have this on their labels usually since it isn't very visible through pictures when buying online.
 * Most cartirdges have a special tri screw holding the cartirdge together as well as a special indention in the middle back of the cartridge.
 * In many cases the chip may be larger than the hole of the game boy advance, this can possibly wreck your video game system. If the chip seems to not go in or it needs extra force, do not bother inserting it into your system.

Why Should I Care?
Well, if you have no moral qualms about purchasing bootleg GBA games there are still genuine reasons to stay away from bootleg games. Bootleg games saved files corrupt easily, making it very common for your saved game to disappear sometimes as soon as a week. Selling bootlegs within the United States is illegal and the seller could get into legal trouble unless they state the game is a bootleg. When buying online from an out of country area legal action becomes harder. A few games also have altered text displayed during gameplay. Also of note is that some bootleg cartridges, such as Pokémon hacks, are actually fan works made by hackers not out for profit, but for fun and as a learning experience, usually incomplete, but are bootlegged onto cartridges by various regions. Notable examples include Pokémon Quartz and Pokémon Chaos Black as fan-works not meant for cartridge distribution.