No! It's definitely not a digestable fiberous carb, it may not be counted as a carb at all but still effect your weight loss. The ingredients may list sugar alchohols and may not even be added to the carb count in the first place.
The sneaky bastards found a way to shove it in there but not count it, even though it can stall your weight loss progress (even while being in ketosis)
Best advice I can give is to stay strict for awhile and away from things with it in there and then gradually add it into your menu to see how it effects you and your weight loss.
Just to give an example, those advantage bars sold by atkins - I could have one and be fine with my ongoing weight loss but if I had the same thing two days in a row, it would cause a small stall in my progress for the week.