Legal privilege protects documents in all civil, criminal, regulatory and investigatory situations, meaning that documents covered by privilege can be seized or disclosed only in certain limited circumstances, strictly controlled by a judge.

With respect to antitrust provisions, agents may gather all information required allowing the authority to ascertain certain infringements. The documentation and information may not be disclosed publicly but the decisions of the authority may refer to this information and documentation in order to be grounded.

Further, under the anti-money laundering legislation, attorneys registered with the Luxembourg Bar have an obligation to report in good faith on any relevant information to the competent Luxembourg authorities.

All information obtained by lawyers defending or representing clients in court (including administrative courts or commissions) and in determining the legal status of clients (including advising clients in preparing or executing transactions) is subject to professional confidentiality.

However, the notes of interviews conducted by an attorney registered with the Luxembourg Bar ("Luxembourg attorney") acting as investigator on behalf of a private company may not be privileged as if the Luxembourg attorney had acted under a client relationship. The Luxembourg Bar has issued recommendations and considered that a Luxembourg attorney acting as investigator for their client may not defend the case because they would be considered as having a conflict of interest. However, the Luxembourg attorney can neither communicate the results of its investigation to third parties nor any documents collected in the course of such investigation, unless expressly authorized by their client.