The deadline for entering the UK national phase of the PCT, or the European regional phase of the PCT is 31-months from the PCT application’s filing or priority date, whichever is earlier.
If the 31-month deadline is missed, then the EPO will issue a notice stating that the European patent application is deemed withdrawn. This notice usually takes a month or so to issue. The applicant then has a period of 2-months, beginning on the date of notification of deemed withdrawal, to enter the European regional phase of the PCT using “further processing”. Further processing involves filing a request, and paying a further processing fee, which is 50% of the official fees, plus a further processing fee (currently €240) in respect of the request for examination.
After the “further processing” period, it may, in a few rare cases, still be possible to apply to restore the application via the “restitutio in integrum” procedure. “Restitutio” is very much a last resort option, and is granted at the discretion of the EPO.
The hurdle that needs to be overcome, for restitutio, is that the application was not filed, despite all due care in the circumstances having been taken. This requires the applicant to have always intended to enter the EPO regional phase, to have made that intention known, and for the applicant and the agent to have had an effective reminder system in place, but despite this, the deadline being missed for an unforeseeable reason. Therefore, simply forgetting the date, a change of mind, or miscalculating the date is insufficient, as that would fail the “all due care” test. Likewise, lack of funds is almost never sufficient excuse for missing the date, unless, somehow, the applicant was actually incapable, e.g. due to a freezing of its bank accounts, by virtue of a Court Order, etc., of paying the fees. On the other hand, acceptable reasons include the death or incapacity of the applicant and/or agent, natural disasters, or circumstances that can be shown to be completely outside the control of the applicant and agent.
If the 31-month deadline is missed, then (unlike the EPO) the UKIPO will not will issue a notice of deemed abandonment. However, the applicant does still have a period of 2-months, calculated from the 31-month deadline, to late-enter the UK national phase, provided the late entry was “unintentional”.
To meet the “unintentional” test, the Applicant must always have intended to enter the UK national phase (a mere intention to obtain a UK patent per se is insufficient, as this could be achieved via the EPO route). In other words, the Applicant must have had an actual intention to enter the UK national phase. As such, actually proving this underlying intention can often be difficult.
If the extended deadline is missed, there is the “last resort” option of applying for restoration: a procedure that mirrors, to a large extent, the EPO’s restitutio procedure outlined above. As per the EPO, the UKIPO’s restoration procedure is discretionary, very much the exception, and carries a very high evidential burden on the Applicant to prove the despite all due care criterion.