Only in that it doesn't incorporate gravity. And given the extremely low energy scale of gravity, it's unlikely to make a difference here. There are extensions

Only in that it doesn't incorporate gravity. And given the extremely low energy scale of gravity, it's unlikely to make a difference here. There are extensions to the Standard Model being used to search for dark matter, but until one of those is actually found experimentally, you can't say that it makes the Standard Model incomplete. It's sound within its domain -- aggravatingly so, since that makes it really hard to figure out what's next.