CH229610 - How to do a compliance check: information powers: rules that apply to all notices: production of documents
You may find that documents supplied in response to an information notice are copies with some details blanked out, or ‘redacted’, often on the grounds that they are irrelevant or unnecessary for the purposes of your compliance check. You usually have the right to insist on seeing the whole of the document, but in some cases the notice may only apply to part of a document, see CH23340.
Note, for example, that redaction is implicit in FA08/Sch36/Para27(2) and could apply where the general ban on audit and tax advice material, in the hands of an auditor or tax adviser is set aside by FA08/Sch36/Para26.
You can, by concession, allow redaction even though you have the right to see the whole of the document.
In some cases it may be clear from the context that some parts of a document contain information which is both confidential and which could not possibly be relevant to the liability you are investigating. For example, a document may be a page from a register which contains other entries besides the one you are interested in. Provided you can be certain that nothing relevant is being hidden from you, you can permit redaction, by concession, in these cases.