In the forthcoming days, a tooltip element (or, more accurately, a span with question mark that displays tooltip content on hover) will be introduced in the VAT number form field. If you are blank template author or use heavy style modifications in forms, you will be on the safe side by hiding these tooltips in advance and by doing necessary changes after release. Tooltip elements will have class form-group-tooltip in 3rd gen templates, in older templates show-tooltip-input.
