# Preserving evidence before you act

Source: https://luatbanquyen.com/en/enforcement/preserving-evidence · Updated: 2026-08-17 · Reviewed: 2026-08-17

The first move is not the warning letter but preserving evidence — content can vanish within hours of the other side learning you noticed.

The commonest mistake on discovering an infringement is reacting immediately — messaging, commenting publicly, firing off a warning. That tells the other side you noticed, and in many cases the material disappears within hours. You win a small skirmish and lose all the evidence for the real case.

## The right order

**Step 1 — Capture the full state.** Screenshots must show the complete URL, the system date and time, and all relevant content. For video, screen-record rather than screenshot. Save the page as PDF to preserve its structure.

**Step 2 — Download a copy** of the infringing material, keeping filenames and metadata intact.

**Step 3 — Record the commercial context.** Is it used to sell something, at what price, with how many views or purchases? This is the data for calculating loss later.

**Step 4 — Have a bailiff record it** if the matter is valuable. A bailiff's record of online content at a fixed moment costs little against the value of evidence that is hard to challenge.

**Step 5 — Assemble evidence of your own right.** The step most often forgotten: you must prove you hold the right before proving the other side infringed it.

## Proving your right

With a **registration certificate** or **protection title** this is trivial — produce the document and the burden shifts to the other side. That is the practical value of registering.

Without registration you must reconstruct the creative process from sources with credible timestamps: original files with creation metadata; version history in your working tools, such as repository commit history or cloud document revisions; emails with clients and colleagues during the work; drafts, sketches and notes; contracts and acceptance records.

What good sources share: timestamps recorded by a third party and hard to backdate.

## IP expert examination

For complex matters — especially confusing-similarity trademark disputes or software — an opinion from an IP examination body carries real weight. It is not a decision of a competent authority, but it is important support in an enforcement request and in a court file.

## What not to do

**Do not post publicly before securing evidence** — you lose the evidence and risk liability if your allegation is wrong. **Do not save only the link**; a dead link is dead evidence. **Do not edit screenshots**, even to crop them neatly — edited images invite challenges to authenticity. **Do not skip proving your own right**; many cases fail there rather than on the infringement itself.

## Cited documents

- [Consolidated document 67/VBHN-VPQH — Law on Intellectual Property](/en/legal-documents/ip-law-consolidated) — In force

## Sources

- [Provisions on IP expert examination and the burden of proof — Điều 201, Điều 203](https://thuvienphapluat.vn/van-ban/So-huu-tri-tue/Van-ban-hop-nhat-67-VBHN-VPQH-2026-Luat-So-huu-tri-tue-700846.aspx) (67/VBHN-VPQH)

- Previous: [Taking down infringing content online](/en/enforcement/online-takedown)
- Next: [Cease-and-desist letters — how to write one that works](/en/enforcement/cease-and-desist-letter)

---

Reference material only; it does not replace legal advice on a specific matter.