I asked if my data was compromised, they said no, but how can I trust/verify this?

This was a targeted attack towards specific individuals, probably carried out by a state actor or someone after data of very valuable individuals. Unless you're one of those (oligarch, etc), you're probably fine.

▲

Maxion 3 hours ago | parent | prev [-]

You can't, really. Banking legislation does not require them to tell you.

▲

orf 2 hours ago | parent [-]

Banking legislation in the UK does require them to tell you for this kind of breach.

	▲	Maxion an hour ago \| parent [-]
		Breach yes, but if they cannot 100% sure identify if your data was given out falsily, then they cannot say. They're not allowed to disclose that they provide your information to LE. So they can only inform you directly if they're 100% sure the specific information request response was sent to false entity. This is very hard to do.