It has been confirmed that the UK’s accession to the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP) has been approved. This means that the UK will soon join a free trade area including Australia, New Zealand, Canada, Singapore, Japan, Mexico, Vietnam, Malaysia, Brunei, Peru and Chile.The Intellectual Property (IP) Chapter of the CPTPP includes an obligation for parties to that treaty to provide a 12-month grace period for patent applications. This means that public disclosures of information should be disregarded as prior art if those disclosures were made by the patent applicant or by “a person that obtained the information directly or indirectly from the patent applicant” during a period within 12 months prior to the filing date of the patent application.That obligation had proven controversial since it is at odds with current practice in the UK which – in line with the European Patent Convention (EPC) – applies a strict ‘absolute novelty’ test. Under the current UK and European approach, parties’ own disclosures can count as prior art against their patent applications, with no grace period provisions except in very limited circumstances such as disclosures in breach of confidence.In fact, questions had even been raised in some quarters as to whether a UK grace period would be compatible with the UK’s continued participation in the EPC. Article 2(2) EPC, which requires EPC contracting states to commit to the requirement for European Patents to “have the effect of and be subject to the same conditions as a national patent granted by that State.”It was questioned whether the introduction of a grace period in the UK – without a parallel grace period in the EPC – would have been consistent with that requirement (despite the fact that a handful of other EPC states already provide 6- or 12-month grace periods for national patent applications and/or national utility models).In the event, any difficulties in reconciling the UK’s membership of both the EPC and the CPTPP have been avoided, as the UK negotiating team has successfully secured a derogation from this part of the IP Chapter. The grace period provisions of the CPTPP have been set aside in the UK “until the necessary amendments to the relevant international conventions have been made”, with an agreement that the UK will “promote international harmonisation on the grace period and will report annually to other CPTPP members regarding progress on this matter.”This means that UK patent practice remains unchanged in this respect, and in contrast to other CPTPP states, patent applicants will not be able to rely on a 12-month grace period when filing UK patent applications.The European Patent Office (EPO) has so far demonstrated no intention to introduce a grace period of its own, and a recent EPO study suggested relatively little support for doing so. The prospect of a change of position in light of the UK’s obligation to ‘promote international harmonisation’ thus seems rather remote at present. According to the Chartered Institute of Patent Attorneys, any adoption of a grace period in the UK may also require amendment of the Strasbourg Patent Convention of 1963, a forerunner to the EPC which is still in force, and to which thirteen EPC member states, including the UK, are signatories.Any developments with respect to amendment of the EPC or the Strasbourg Convention will be monitored with interest, but the adoption of a grace period in Europe seems unlikely for the time being.