The key is whether those businesses on the list have opted out of the Data Protection Act. The DPA imposes penalties on the dissemination of information without the consent of the person/business.
You will notice when you sign up to things online that there is nearly always a box stating "please tick if you do not wish your information to be passed to our trusted affiliates for marketing purposes".This is what this is for, if the user does not tick this box then they have in effect foregone their right to data protection.
If you have something similar or that has the same effect from your dealings with those on the list then you probably can sell it. I would tread very carefully, particularly when considering the sale of a person's details, because you can be liable for a fine of £5, 000.00 per person if you do not have their permission and possible criminal sanctions
If you are in any doubt then you should consider an (e)mail-shot specifically asking those on the list for their permission to sell on their details to a trusted affiliate.If they reply in the affirmative then you are on safe ground. If they do not reply or refuse then I certainly would not sell them on.
Clearly, you should avoid giving information on banking details away, I would even steer clear of payments methods personally.
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