A recent High Court decision demonstrates that, whilst
confidentiality is a prerequisite to a claim for privilege,
information will not cease to be confidential unless it is in fact
known to a "substantial number of people": Winstone v MGN Ltd [2019]
EWHC 265 (Ch).
In the present case, the court found that the quality of
confidentiality had not been lost where the contents of the
privileged material had come into the hands of a small group of
investigative journalists and at least one investor, and may have
(though the evidence did not establish that it probably did) come
into the hands of others.
The decision is consistent with previous judgments which suggest
that the courts may take quite a robust view as to when privileged
material has (or has not) entered the public domain, so as to lose
the requisite quality of confidentiality, particularly where the
privileged material has been obtained in breach of confidence (see
this post) or through inadvertence (see
