Data Mining

The issues

Is it permitted for a company to make use of "data-mining", where personal information held in relation to individuals in order to extrapolate further information about their private affairs?
Is it permissible for a company to sell such information to third parties without the data subjects' awareness of this activity?
(see Aaron Levene, Case Studies in Jewish Business Ethics, pp. 69-74).

The Jewish Perspective

It would seem that data-mining is prohibited from the Jewish perspective as an invasion of privacy and as an inappropriate use of confidential information. It would be further prohibited to sell this on to a third source (a) through the prohibition of having benefit from confidential information;
(b) through the prohibition of spreading gossip.
This prohibition of spreading gossip applies not only to untruths but also to the passing on of any information, regardless of its false or possibly derogatory nature, since it is a prohibition upon even the mere passing on of information about one person to another.