What evidence should I preserve before sharing a pitch deck, prototype or technical document?

Preserve the version that will actually leave your hands

Set aside a copy of the final sharing package before sending it. Include the deck, attachments, technical drawings and any supporting document the recipient will receive. Give the package a reference that also appears in your covering message.

Keep editable source files separately from the exported presentation. Both can matter: the export shows what you disclosed, while the source and earlier revisions help explain how it developed. If you remove confidential slides for an introductory meeting, preserve that shorter deck as its own version rather than assuming the full deck records the disclosure.

For a physical prototype, keep photographs, identifying marks, relevant drawings and a description of its condition and capabilities. Record what the recipient may handle or inspect. A photograph documents a view of the object; it cannot establish every feature of the prototype or what a live demonstration revealed.

Keep enough history to explain the work

Retain the earlier records that explain important choices: a sketch, test result, design revision or contribution note. Connect them to the people involved and the agreements relevant to their work. You do not need to send this whole history to the recipient.

A timestamp can support the chronology of a preserved file. As RFC 3161 explains, the underlying assertion concerns data existing before a particular time. It does not establish who created that data or whether its statements are correct.

Keep certified originals separate from everyday working copies. The article Your certificate is immutable. Your files are not. explains why preserving the exact bytes matters even when two documents look identical.

Decide the terms before disclosing the detail

Record the intended recipient, their organisation and the purpose of the exchange. Keep the applicable NDA or other terms, including the version agreed and the record of agreement. Check whether the recipient can involve colleagues or advisers and whether oral disclosures need written confirmation.

The UK Intellectual Property Office’s NDA guidance recommends defining the permitted purpose and keeping a record of disclosures. The particular agreement and applicable law determine the obligations.

If an investor will not sign an NDA, decide what you can show without one. A limited introductory deck may be enough to start a discussion. Timestamping a detailed deck does not make disclosing its contents confidential. For the wider tension between demonstrating value and revealing know-how, see IP-backed finance and the disclosure paradox.

Where the material includes a potentially patentable invention, resolve the filing and disclosure sequence first. Under Article 54 of the European Patent Convention, public disclosure before filing can affect novelty. A private timestamp does not reserve a patent filing date.

Complete the record after the exchange

Save the sent message, attachments, portal receipt or available access records. For a meeting, note who attended, which version you presented and what additional information you explained or demonstrated. Distinguish notes made immediately afterwards from later recollections.

Record a revised deck, follow-up answer or additional demonstration as a further disclosure. Your record should let someone reconstruct this particular exchange, rather than merely show that a project folder existed.