Medical Device Design-Around in China: FTO Notes That Engineering Will Actually Use

Life Sciences & Healthcare Blog · Legal cluster

Engineers ask "can we ship?" and lawyers answer with claim charts. The niche skill that actually protects a Chinese medical-device company is a freedom-to-operate (FTO) note that changes computer-aided design (CAD) decisions before tooling is cut — not a memo that arrives after the mould is paid for. This article explains how to turn FTO analysis into operational design guidance under the Patent Law of the People's Republic of China, how to document a design-around defensibly, and where the analysis must coordinate with patent linkage, trade-secret discipline, and the cost-down redesigns triggered by volume-based procurement (VBP).

Why this matters: the FTO memo is a design document, not a legal artefact#

Medical-device development runs on long lead times and irreversible commitments. Once a company cuts tooling, builds inventory, and files registration files with the National Medical Products Administration (NMPA), a claim-chart showing infringement risk is no longer a design input — it is a crisis. The purpose of FTO work in the device industry is to find infringement risk while the design is still soft: while the engineer can change a bearing, relocate a sensor, alter a valve geometry, or substitute a material without costing months of work. That is why the FTO memo must be written for the engineering reader, with claim charts translated into design constraints, and with the alternatives already vetted for performance.

The commercial stakes have grown because of China's VBP programme. When volume-based procurement forces a device maker into a sharp cost-down redesign, engineering teams reach for the cheapest available copy of a competitor's geometry. Cheap copies attract two problems simultaneously: patent infringement claims and product-quality claims. The redesign that looks like a bargain on the purchase order becomes a liability in both the IP file and the device-safety file. FTO is not a luxury at that moment; it is the gate that keeps a cost-down redesign inside the law.

Governing legal and statutory framework#

Patent Law of the People's Republic of China (2020 amendment)#

Article 11 of the Patent Law grants patentees the exclusive right to prevent others from making, using, offering to sell, selling, or importing the patented product without authorisation. For a device company, that means the design must avoid the claimed subject matter of blocking patents — not merely the patent family with the loudest marketing presence. Article 69 (as renumbered in the 2020 amendment) provides a limited experimental-use exemption, which shelters research and experimental use of the patented technology but does not shelter commercial manufacture. The commercial embodiment is the test, and the FTO memo must therefore focus on the patents that read on the product the company intends to sell, not on every member of a broad patent family.

Article 11: After the grant of a patent right for an invention or utility model, except as otherwise provided for in this Law, no unit or individual may, without the authorization of the patentee, exploit the patent, that is, may not make, use, offer to sell, sell, or import the patented product, or use the patented process, or use, offer to sell, sell, or import the product directly obtained by the patented process, for production or business purposes.

SPC Judicial Interpretation II on Patent Infringement Cases#

The Supreme People's Court's Interpretation on Several Issues concerning the Application of Law in the Trial of Patent Infringement Cases (II) governs how claims are construed and how the doctrine of equivalents is applied in Chinese courts. The interpretation matters to a design-around because courts apply equivalence analysis beyond literal infringement: a design that substitutes a technically equivalent feature with no substantial difference in function, effect, or approach can still infringe under the doctrine of equivalents. A design-around must therefore change the claimed feature in a way that is not a mere equivalent substitution. The engineering change needs a documented functional rationale — a different solution to the underlying problem — not just a cosmetic swap.

Key legal analysis and enforcement precedents#

Chinese courts have repeatedly analysed blocking-patent strategies in the device and electrical sectors. The well-known Chint v. Schneider Electric case illustrates how a patent holder uses a narrow but enforceable patent to block a commercial design choice; the litigation history — including the record statutory damages award later adjusted on appeal — remains a standard reference for how seriously courts take the commercial embodiment. The lesson for device designers is that the blocking patent does not need to be elegant; it needs to read on the product that sells.

The Supreme People's Court IP Court, which handles substantial patent appeals, has developed a consistent approach to claim construction and equivalence in mechanical and electromechanical devices. Its decisions repeatedly reward design changes that solve the technical problem differently and penalise changes that merely rearrange features without changing the functional solution. For an FTO note, the practical consequence is a two-part test for every proposed alternative: (1) does it avoid the literal claim language, and (2) does it avoid the doctrine of equivalents by employing a different technical approach, not just a different physical arrangement? An alternative that fails the second part is not a design-around; it is an invitation to sue.

Enforcement practice in the medical-device field adds a cross-border dimension. A device designed in China, manufactured by a Chinese contract manufacturer, and sold into the United States or the European Union can be challenged under the patent laws of multiple jurisdictions, and a design that is clean in China may still infringe abroad. The FTO note for an export-oriented device should therefore flag jurisdiction-specific claim differences, particularly where the US or EU patent family is broader than the Chinese family.

Claims construction is where FTO memos succeed or fail. A Chinese court construes the claims of a patent by reference to the specification and the claims themselves, and the FTO analyst must read the blocking claim at its narrowest credible reading and its broadest credible reading. The commercial embodiment is compared against both: if it falls outside even the broad reading, the design is clean; if it falls within the broad reading but outside the narrow one, the design is a litigation question, not a clearance. The memo should state which reading it used and why, because the same analysis will be tested later in a different forum.

Operational vulnerabilities and transactional pitfalls#

The common failure modes in device FTO practice include:

• Prioritising the wrong patents: the FTO memo reviews every family member and buries the two or three patents that actually block the commercial embodiment under a mountain of citations. Engineering cannot act on noise.
• Cosmetic design-arounds: the engineer moves a feature, renames a component, or changes a dimension without changing the technical approach, believing that "different-looking" means "non-infringing." Courts under the doctrine of equivalents will not agree.
• Trade-secret leakage in documentation: the FTO memo candidly describes the company's process know-how — manufacturing tolerances, material recipes, yield tricks — in a document that may be produced in litigation. Filing a document that teaches your own trade secrets is a self-inflicted disclosure.
• Ignoring the cost-down redesign: the device passes FTO at initial release, then VBP forces a redesign, and the redesign copies a competitor's cheaper geometry without a fresh FTO pass. The new design ships with unexamined infringement risk.
• Treating FTO as a one-time event: patents are granted, amended, and invalidated continuously. A competitor's granted patent that did not exist at the original FTO date may block the product two years later. The note needs a refresh trigger, not a single date stamp.

FTO notes from the Suzhou device corridor#

In my medical-device and FTO-coordination practice in Suzhou, the design-around conversation starts at the right moment — while the design is still soft, before tooling is cut — and that is the moment that decides whether the FTO memo is a design input or a crisis. The recurring failure is not the absence of FTO work; it is the shape of the memo. The memo that reviews every patent family member and buries the two or three claims that actually block the commercial embodiment under a mountain of citations is noise, and engineering cannot act on noise. The cosmetic design-around — moving a feature, renaming a component, changing a dimension without changing the technical approach — fails the equivalence analysis that Chinese courts apply under the SPC’s judicial interpretation, because a design that substitutes a technically equivalent feature still infringes. The blocking-patent triage is the discipline that works: mark the claims that read on the product’s architecture and headline features, translate each into a design constraint the engineer can act on, and gate every cost-down redesign through the same analysis. The NMPA file adds a China-specific layer: the registration and clinical-evaluation requirements mean the design is locked earlier, so the FTO read must come before the registration file is built. My advice is to write the memo for the engineer, not for the lawyers: a short list of blocking claims, each stated as a constraint, with the equivalence risk called out in plain language.

Strategic compliance roadmap and action plan#

An operational FTO programme for a medical-device company runs on five disciplines:

1. Blocking-patent triage: within the identified patent families, mark the claims that read on the commercial embodiment — the product's architecture, core function, and headline features. Engineering acts only on this short list.
2. Design-constraint translation: for each blocking claim, write the claim as a design constraint: "the sensor must not be mounted coaxially with the drive shaft," "the sealing surface must not use a compliant ring in this configuration." The engineer can act on a constraint; a claim chart alone is a filing, not a design input.
3. Alternative vetting with the equivalence test: for each proposed alternative, document why it solves the technical problem differently — different structure, different principle, different functional result — so the file answers the doctrine of equivalents before it is asked.
4. Trade-secret hygiene: separate the FTO memo's public-facing claim analysis from the process-know-how notes; mark know-how documents as confidential and control distribution; never embed a process recipe in a document destined for an external audience.
5. Redesign trigger: re-run FTO whenever the design changes materially — cost-down redesigns under VBP, new material sourcing, new target markets, new grant notices from competitors. The refresh is cheap; the litigation it avoids is not.

Document everything: the alternatives considered, the reasons they were rejected, the performance data supporting the chosen design, and the date of each FTO refresh. When a competitor later alleges infringement, the design file is the defence — it shows deliberate, documented avoidance of the claimed subject matter, not accidental proximity.

The FTO refresh should also cover the registration file, because in medical devices the patent risk interacts with the NMPA registration and, for export, with the target market's regulatory review. A device design that avoids the blocking patent but changes the performance characteristics may require new testing, new clinical evaluation, or a new registration variation, and the timing of those steps determines whether the design-around is commercially viable. The memo should therefore include a regulatory-impact column: for each proposed alternative, what does it cost in retesting, re-registration, or new certification, and when must that work start so that the design-around does not simply trade an IP problem for a regulatory delay.

What not to do#

Do not wait for tooling to ask whether the design is clear. Do not write the FTO memo for lawyers only — the engineer must be able to act on it. Do not let a cost-down redesign bypass the FTO gate because it is "just a copy of what everyone else does" — copying the market leader is precisely when the blocking patent bites. And do not describe your own trade secrets in a memo that might be handed to the other side. The FTO note that changes CAD decisions before tooling is cut is worth its weight in settlements avoided; the FTO note that arrives after the mould is a post-mortem.

Read next: Patent linkage (drugs) · Trade secrets · Device liability (quality after redesign)

Cluster: Life sciences legal hub · Life sciences blog