European divisional applications under Rule 36 EPC

Rule 36: any pending earlier application

Rule 36(1) EPC says simply that the applicant may file a divisional application relating to any pending earlier European patent application. That wording dates from 1 April 2014 (decision CA/D 15/13). Between 1 April 2010 and 31 March 2014, divisionals were subject to time limits under Rule 36(1)(a) and (b), counted from the examining division's first communication. The EPO told applicants to disregard any information about those time limits after 31 March 2014 (OJ EPO 2014, A22), but older articles still repeat them.

The same change introduced an extra fee for divisionals divided from divisionals (Rule 38(4)). A "first generation" divisional is divided from a root application that is not itself a divisional; a second generation is divided from a first generation, and so on (Guidelines A-IV, 1.1.2). A parent may have any number of divisionals.

When is the parent "pending"?

Pendency is a substantive condition, not a time limit, so further processing and re-establishment cannot rescue a divisional filed too late (Guidelines A-IV, 1.1.1). The cases:

Rule 134, which extends periods ending on a day the EPO is closed, does not apply to pendency (A-IV, 1.1.1). The last day is simply the day before the mention of grant, so file online well before it.

Filing: who, where and in what language

• Only the applicant on record for the parent can file, and all co-applicants jointly. A buyer of the parent must have the transfer registered first (A-IV, 1.1.3).
• File directly with the EPO, online or at Munich, The Hague or Berlin. Filing at a national office has no legal effect (Article 76(1), Rule 36(2)).
• Use the language of the proceedings of the parent. If the parent was filed in another language, you may file in that language and translate within 2 months (Rule 36(2)).
• Indicate on Form 1001 that it is a divisional, the parent's number and the generation.
• All states designated in the parent when you file are designated in the divisional (Article 76(2)). States already withdrawn from the parent cannot come back.
• Claims can follow later; the divisional only needs to meet the filing date requirements of Rule 40(1) while the parent is pending (A-IV, 1.2.1).

Fees, including second and later generations

A divisional pays the fees of a new application. The filing fee and search fee are due within 1 month of filing, or the divisional is deemed withdrawn (Rule 36(3)). The search fee is due even if you paid a further search fee for the same invention in the parent, though part of it may be refunded when the EPO can reuse an earlier search (Article 9(2) of the Rules relating to Fees). The designation fee is due 6 months after the Bulletin mentions the divisional's own search report (Rule 36(4)), the same period as the examination fee.

The additional fee is part of the filing fee, so it shares its 1-month deadline. Claims fees (€290 each from the 16th claim) are due again in the divisional even if paid in the parent (A-IV, 1.4.2).

Back renewal fees

This is usually the largest cost. Renewal years for the divisional count from the parent's (or root's) filing date, and every renewal fee already due on the parent falls due again on the divisional's filing date (Rule 51(3)). You have 4 months to pay them without surcharge, and any renewal fee falling due within those 4 months can be paid in the same window. After that, a 50% surcharge applies up to 6 months. Further processing is not available for renewal fees. A divisional filed in the 7th year owes years 3 to 7 at once: €5,250.

The Article 76 added-matter trap

Article 76(1) allows a divisional only for subject-matter that does not extend beyond the content of the earlier application as filed. The test is the same as for amendments under Article 123(2): everything must be directly and unambiguously derivable from the parent as filed (Guidelines C-IX, 1.4; G 1/05). Four ways applicants fall into it:

1. Copying the amended parent. If you file the divisional with the parent's description as amended during examination, any wording added in prosecution must still trace back to the parent as filed. Starting from the parent as originally filed avoids that.
2. Intermediate generalisation. Taking one feature out of a specific embodiment without the features it was disclosed with is added matter in a divisional just as in an amendment.
3. Chains. In a sequence of divisionals, the content must be derivable from each preceding application as filed (G 1/06). Matter dropped from a first-generation divisional on filing cannot be revived in a second-generation one.
4. A partial take. If the divisional claims only part of what the parent claimed, that part must be disclosed in the parent as a separate entity usable outside the parent's invention (T 545/92).

The consequences: the search may be limited under Rule 63 where claims break Article 76 (Guidelines B-VIII, 3), and the examining division will refuse the divisional under Article 97(2) unless you delete the added matter. You may do that by amendment even after the parent has ended (G 1/05), but the divisional cannot be converted into an application with its own date. Later amendments to the divisional must also satisfy Article 123(2) against the divisional as filed.

Separately, parent and divisional must not claim the same subject-matter (Guidelines C-IX, 1.6). The prohibition on double patenting was confirmed by the Enlarged Board in G 4/19 (G-IV, 5.4). One application may claim its subject-matter A in combination with the other's B, but not the same claim in different words.

Timing strategy

• After a unity objection. If the search report covers only the first invention because you did not pay further search fees (Rule 64), or the examiner objects under Article 82 (unity of invention), the parent must be limited to one invention and Rule 137(5) bars switching to the unsearched one. A divisional is the way to pursue the others. You choose when to file; there is no special deadline.
• After the Rule 71(3) communication. The commonest moment. The parent is about to grant with narrowed claims, and a divisional keeps broader or different claims alive. File it before the mention of grant; the parent can still grant on schedule.
• After a refusal. You can file within the 2-month appeal period without appealing (G 1/09). The divisional then has to overcome the same objections with different claims.
• Keeping a family pending. A pending divisional lets you later claim features of competitors' products, within the parent's original disclosure. Each generation costs more, the back renewal fees grow every year, and the 20-year term still runs from the root filing date.
• Delete without abandoning. Deleting subject-matter from the parent does not stop you dividing it out later, but avoid statements that read as abandoning it (Guidelines C-IX, 1.3).

Each granted divisional is a separate European patent, so you decide separately whether to validate it nationally or request unitary effect. Divisionals are searched, published and examined like any other application; see our guide to the European patent application for those stages and the European search report for the search opinion you will receive.

Worked example

A parent application was filed on 10 March 2023. On 15 September 2026 the EPO sends a Rule 71(3) communication for narrow claims to a sensor housing. The applicant wants to keep pursuing broader claims to the mounting bracket described in the parent as filed, and files a first-generation divisional online on 2 November 2026 with 18 claims, before replying to the Rule 71(3) communication.

• By 2 December 2026: filing fee €135 and search fee €1,595 (€1,730), and claims fees for three claims over 15 (€870). No generation fee for a first generation.
• By 2 March 2027: the renewal fees already paid on the parent for the 3rd year (due 31 March 2025) and 4th year (due 31 March 2026): €725 + €885 = €1,610, without surcharge under Rule 51(3).
• 31 March 2027: the 5th-year fee (€1,050) falls due on the normal schedule, since that is after the 4-month window.
• 6 months after the Bulletin mentions the divisional's search report: designation fee €720, examination fee €2,010 and the reply to the search opinion.

Official fees to reach examination: €6,940, plus the 5th-year renewal. The parent grants as planned. If in 2029 the applicant divides again from this divisional (a second generation), it pays €370 filing fee including the €235 additional fee, and the back renewal fees by then reach at least €3,875 for years 3 to 6, assuming it files before the 7th-year fee falls due on 31 March 2029.

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