## Facts

- The European Patent Office (EPO) granted Lenzing AG a European patent designating, among other states, the United Kingdom, creating a “European patent (UK)” under the Patents Act 1977.
- Courtaulds plc (and related Courtaulds entities) attacked the patent on two tracks:
  - In the UK Patents Court, Courtaulds sought revocation of the European patent (UK), and Lenzing counterclaimed for infringement.
  - In the EPO, Courtaulds filed a timely opposition to the European patent.
- The EPO Opposition Division rejected the opposition and maintained the patent.
- Courtaulds appealed to an EPO Board of Appeal (BoA), which reversed the result and revoked the patent, doing so quickly and without giving reasons acceptable to Lenzing.
- Following notification of the EPO revocation, the UK Patent Office (acting through the Comptroller) recorded the revocation on the UK register.
- Lenzing alleged serious unfairness in the BoA procedure and argued the BoA revocation should be treated as a nullity in the UK.
- Lenzing brought collateral challenges in England, including:
  - a judicial review claim aimed at the Comptroller’s entry (and, in substance, at the EPO revocation), and
  - a Patents Court claim seeking rectification of the register so the patent would appear in force, allowing infringement proceedings to continue.
- The High Court (Queen’s Bench Division and Patents Court) heard the public law and patent law matters together.

## Issues

1. Whether an English court has jurisdiction to review, or treat as void, an EPO Board of Appeal decision revoking a European patent.
2. Whether, once the EPO notifies revocation, s 77(4) of the Patents Act 1977 requires the European patent (UK) to be treated as revoked without any UK inquiry into alleged procedural defects at the EPO.
3. Whether the Comptroller’s act of recording EPO revocation on the UK register can be set aside by judicial review on the ground that the underlying EPO decision was procedurally unfair.
4. Whether the Patents Court’s power to rectify the register can be used to reverse the legal effect of an EPO revocation reflected in the register.
5. Whether TRIPS (including Article 32 and related provisions on review) requires a further opportunity for judicial review in UK courts of an EPO revocation decision.

## Decision

- The court rejected Lenzing’s collateral attacks and refused relief that depended on treating the patent as still in force in the UK.
- English courts cannot sit in judgment on the acts of the EPO (an international organisation created by treaty), including a BoA revocation decision.
- For purposes of s 77(4) Patents Act 1977, it was enough that the EPO, acting in purported exercise of its EPC powers, revoked the patent; UK law then treats the European patent (UK) as revoked.
- The Comptroller’s role in entering the revocation on the UK register was administrative; the Comptroller had no power or duty to investigate the regularity or fairness of the EPO proceedings.
- Register rectification could not be used to contradict the statutory consequence that an EPO revocation has in UK law.
- TRIPS did not give Lenzing a right to obtain a fresh review of the EPO’s revocation in UK courts; the EPO appeal structure satisfied the requirement for review by a judicial or quasi-judicial body, and TRIPS did not have domestic effect to expand UK jurisdiction in this context.

## Legal Principles

- Decisions of EPO Boards of Appeal revoking a European patent are not justiciable in English courts; collateral challenges to their validity or procedure are not permitted.
- Under s 77(4) Patents Act 1977 (implementing the EPC), once the EPO revokes a European patent in purported exercise of its Convention powers, the European patent (UK) is treated as revoked as a matter of UK law.
- The phrase “revoked in accordance with the Convention” in s 77(4) does not authorise an English court to review whether the EPO complied with EPC procedure or standards of fairness when reaching revocation.
- The Comptroller’s register entry recording EPO revocation is not a discretionary decision on validity; it records the legal consequence of the EPO act and cannot be attacked by challenging the merits of that act.
- The court’s register-rectification jurisdiction cannot be used to reinstate a European patent (UK) after an EPO revocation that UK law must recognise.
- TRIPS does not require an extra layer of national-court review of EPO revocation decisions, and it does not, without implementing legislation, confer a domestic right to challenge such decisions in England.

## Conclusion

The High Court held that the EPO Board of Appeal’s revocation automatically brought the European patent (UK) to an end under s 77(4) of the Patents Act 1977, leaving no room for English judicial review or register rectification based on alleged unfairness or error in the EPO process, and TRIPS did not create a further UK right of review.


Lenzing AG's European Patent (UK), [1997] RPC 245 (1997)