According to Torrentfreak, Sky have an agreement with FACT, a private, limited company, to disclose details of Sky subscribers without any court order whatsoever.
"Initially FACT had considered that an account might have been held with comms provider BSKYB so wrote to the company asking for information – FACT apparently have “an agreement” with BSKYB to obtain information."
"BSKYB responded back saying no accounts were held at the Vickerman’s address"
Are you happy to have your details passed on to a third-party without your consent or any official court order?
Sky don't seem to be too bothered about protecting their customers' details.