If a reseller of products from ABC Ltd is saying that they are selling products from ABC Ltd then then would be telling the truth.
If they try to make it look like they are ABC Ltd or make it look like their site is ABC Ltd's site then they may be crossing boundaries.
Don't think that Google are likely to pick up on this sort of thing at this level and the local trading standards or equivalent would probably be the best course of action if ABC Ltd feel agrieved.