In trade secret litigation, the hardest part is rarely the law — it is evidence. Unlike patents or trademarks backed by a certificate, a trade secret has no “birth certificate”: everything must be proven from scratch. This article maps the four mandatory evidentiary links under Article 203 of the Law on Intellectual Property (VBHN 67/VBHN-VPQH) and two procedural tools that help plaintiffs overcome evidence gaps.
1. Foundational principle: no reversal of the burden of proof for trade secrets
Article 91.1 of the 2015 Civil Procedure Code requires a party seeking court protection of its lawful rights and interests to “collect, provide and submit to the court documents and evidence proving that the claim is well-founded and lawful” — except for certain special cases, and trade secret disputes are not among them.
A critical distinction: Article 203.4 of the IP Law reverses the burden of proof only in lawsuits over infringement of a process patent (the defendant must prove its process differs from the protected one). Never write or imply that “the defendant must prove it did not infringe the trade secret” — the plaintiff carries the full burden.
2. The four evidentiary links the plaintiff must prove
(a) The information is a trade secret — proving all three Article 84 conditions: not common knowledge and not easily obtainable; conferring a business advantage when used; kept confidential through necessary measures. In practice this link “breaks” most often: many plaintiffs cannot show they applied necessary confidentiality measures (see our article on employee NDAs).
(b) The plaintiff is the lawful holder/manager — Article 203.2(b) requires “evidence necessary to prove rights in the trade secret” (there is no certificate to produce); combined with Article 121.3 (lawful acquisition + keeping it confidential) and Article 127.2 (lawful controllers include the owner, lawful assignees, and managers).
(c) An infringing act occurred — Article 203.3 requires proof of the infringing act, measured against the six act groups in Article 127.1: (a) defeating confidentiality measures to access or collect; (b) disclosing or using without permission; (c) breaching a confidentiality contract or deceiving, instigating, bribing, coercing, enticing or abusing the trust of a person under a confidentiality duty; (d) obtaining through licensing procedures; (dd) using or disclosing despite knowing or having a duty to know of the unlawful origin; (e) failing to keep test-data confidential (Article 128).
(d) Actual damage — if damages are claimed, actual loss must be proven under Article 203.6 by reference to Article 205. The causal link between the act and the damage is one of the two hardest things to prove in these cases.
3. Practical evidence checklist per link
The following are practical suggestions, not a statutory list — “necessary evidence” in Article 203.2(b) is an open concept:
- Proving trade-secret status: internal documents marked “confidential”; information-classification rules; signed NDAs with employees and partners; system access logs; confidentiality training records.
- Proving lawful holding: labor contracts, assignment contracts, handover minutes; decisions assigning management of confidential information; emails and documents evidencing the investment that created the information.
- Proving the infringing act: emails, messages, abnormal access logs; witness testimony; industrial property expert opinions (Article 201 — an evidence source recognized by law); goods or documents showing use of the confidential information.
- Proving damage: financial statements, lost contracts, revenue gaps; remediation costs; damage valuations.
4. Two procedural “problem-solvers”
- Compelling the other party to produce evidence (Article 203.5): where relevant evidence is controlled by the other party and inaccessible to the plaintiff, the court may be asked to order the controlling party to produce it. Highly practical: emails, files and access logs usually sit with the defendant.
- Provisional urgent measures (Articles 206–207): where there is a risk of irreparable damage, or evidence/goods risk being dispersed or destroyed — the court may order seizure, distraint, sealing, or prohibitions on altering the status quo. The applicant must post security of 20% of the value of the goods subject to the measure, or at least VND 20,000,000 (Article 208.2), or present a bank/credit-institution guarantee.
5. Calculating damages — Article 205
Article 205.1 sets the bases for damages: (a) total material loss in monetary terms plus profits the defendant earned from the infringement (if not already counted in the material loss); (b) the license price on the assumption the defendant had been lawfully licensed; (c) another calculation method proposed by the right holder in compliance with law; (d) if none of (a), (b), (c) can be determined, the court decides an amount not exceeding VND 1 billion. The right holder may also claim reasonable lawyer’s fees (Article 205.3).
6. Channels for handling trade secret infringement
- Civil: sue in court for cessation and damages (Article 202).
- Administrative: request handling under Decree 99/2013/ND-CP (as amended by Decrees 126/2021, 46/2024 and 186/2026/ND-CP, effective 15/7/2026); maximum fines of VND 250,000,000 for individuals and VND 500,000,000 for organizations (Article 2, Decree 99/2013).
- Provisional urgent measures of the court (section 4).
- Competition channel: infringement of confidential business information is simultaneously a prohibited act of unfair competition (Article 45.1, 2018 Competition Law; Article 130, IP Law).
Note on criminal handling: Article 226 of the 2015 Penal Code (amended 2017) covers crimes infringing industrial property rights, but its scope and quantitative thresholds were not checked against the original text for this article — consult the Penal Code in force directly; do not infer from this article.
7. Mistakes that make plaintiffs lose
- Failing to prove confidentiality measures (the Article 84.3 link) — the most common failure; fix it with NDAs and internal confidentiality rules before any dispute.
- Waiting until litigation to gather evidence — while logs and emails may already be deleted; not seeking provisional urgent measures in time.
- Assuming the defendant must prove its innocence — the no-reversal principle (section 1).
- Claiming damages without proving actual loss and causation.
Limitation note: the civil limitation period follows the 2015 Civil Code — Article 429 provides 03 years from the date the entitled person knew or should have known of the infringement of their lawful rights and interests.
FAQs
Must the defendant prove it did not infringe the trade secret?
No. There is no reversal of the burden of proof in trade secret disputes; the plaintiff must prove all four links.
Can I sue without an NDA?
In principle yes, but proving “confidentiality through necessary measures” (Article 84.3) becomes very difficult — the link that breaks most often.
What if the evidence is in the defendant’s hands?
Ask the court to apply Article 203.5 to compel production; consider provisional urgent measures (Articles 206–207) in parallel.
Maximum damages when loss cannot be quantified?
The court decides, capped at VND 1 billion (Article 205.1(d)), plus reasonable lawyer’s fees.
Legal sources cited
- Law on Intellectual Property — VBHN 67/VBHN-VPQH (23/3/2026): Articles 84, 121.3, 127, 128, 130, 201, 202, 203, 205, 206–208.
- 2015 Civil Procedure Code: Article 91.1.
- 2015 Civil Code: Article 429 (limitation period).
- Decree 99/2013/ND-CP (amended by 126/2021, 46/2024, 186/2026 effective 15/7/2026): Article 2.
- 2018 Competition Law: Article 45.1.
See also: Protecting Trade Secrets with Employee NDAs in Vietnam: Key Clauses — build your evidentiary “fence” of confidentiality measures today.
Need advice on gathering and preserving evidence or filing a trade secret lawsuit? Reach FLAT Law Firm via the Contact page.
The information above is for reference only and does not constitute legal advice.
Transparency note: This article was drafted by FLAT Law Firm\u2019s AI content production system and reviewed by the internal review board (AI Legal Council QA). It has not been reviewed by a human lawyer.
