If you receive a hack in the GTS and then breed it, is the egg considered legit according to the game data?
Basically in Black I would receive rare Pokemon like Spiritomb and Zorua through GTS. I always questioned the legitimacy of the Pokemon so I would breed it and toss the traded Pokemon. I know it's naive to think most Pokemon are legit on GTS but it's really the only method of going about getting a Pokemon that is rare.
According to the game data, yes, and the Pokémon itself will obviously pass hack checks. I can't guarantee your game card itself will pass the general check after possibly coming into contact with a hacked Pokémon, but if you release it, then the chance is quite high. Only way to be 100% sure is to trade and breed on a secondary card (say, X, in case your main game is Y), while hatching the resulting egg on the card you intend to use (Y in this example). --- Platinum FC: 2063 1730 8794; HeartGold FC - 0560 9058 5184; Diamond FC - 3179 2247 2864; Black FC - 2279 2860 5022; White FC - 3138 5784 9025