Patent Prosecution Highway (PPH)

The Patent Prosecution Highway (PPH) is a bilateral and multilateral framework that allows patent applicants to request accelerated examination at one patent office based on a favorable examination result from another patent office. The core idea: when a patent application receives a positive examination result at one patent office — for example, the USPTO issues a Notice of Allowance indicating that claims are novel, non-obvious, and enabled — the applicant can request that another participating patent office (for example, the Japanese Patent Office, or KIPO in Korea) fast-track the examination of a corresponding application. Instead of waiting years for the second office to independently conduct its own prior art search and examination, the second office uses the first office's work product as a starting point. The result: examination that might normally take 18–30 months at a foreign office can often be completed in 2–6 months under PPH. How PPH was created: the first PPH bilateral pilot was launched in May 2006 between the USPTO and the JPO. The pilot demonstrated that when one major patent office allows claims, those claims are also allowed by other offices at a high rate — reflecting that most rejections are resolved at the first office. The success of the US-Japan pilot led to widespread bilateral agreements, and eventually to the Global PPH (multilateral) launched in January 2014. What PPH is NOT: PPH is not a guarantee of allowance. The Office of Later Examination (OLE) — the office receiving the PPH request — independently examines the application. PPH simply moves the application to the front of the examination queue and signals that a trusted foreign office found the claims acceptable. The OLE may still reject claims, object to the specification, or issue other Office Actions. PPH is not an international patent — it accelerates examination at individual national offices; each national patent is still granted separately under each country's laws.

Filing a PPH request at the USPTO (as the Office of Later Examination) involves these steps: (1) Obtain a favorable result from an eligible Office of Earlier Examination (OEE): the USPTO accepts PPH requests based on allowances or positive opinions from any Global PPH participating office, plus various bilateral PPH partners. A positive WO-ISA from any PCT ISA (including the EPO, JPO, KIPO, IP Australia as ISA) qualifies for PCT-PPH at the USPTO. (2) Amend your US claims to correspond to the OEE-allowed claims (equal or lesser scope): make sure every independent and dependent claim in your US application is limited to subject matter within the scope of the OEE-allowed claims. Prepare a claim correspondence table (one column: OLE claim number; second column: corresponding OEE claim number(s)). (3) File the PPH request electronically via EFS-Web/Patent Center. The request consists of: a cover letter identifying the OEE and the application numbers; the claim correspondence table; copies of the OEE-allowed claims; copies of the OEE Office Action showing the favorable result; copies of documents cited by the OEE (if any). (4) No government fee: PPH requests at the USPTO are currently free of charge (no additional USPTO fee beyond normal filing and maintenance fees). (5) Timing: file BEFORE the USPTO issues a first Office Action. Check application status on Patent Center; if no Office Action has issued, PPH is still available. (6) After PPH request: the USPTO examiner reviews the request and typically issues a first Office Action within 2–6 months — compared to 18–24 months for a standard application. The examiner is directed to first consider the OEE's search results and may adopt the OEE's reasoning, reducing the number of rejections.

'Claims must correspond' is the central substantive requirement for PPH. It means that every claim in the Office of Later Examination (OLE) application must be of EQUAL OR LESSER scope than a claim that was favorably examined by the Office of Earlier Examination (OEE). In practice: if the JPO allowed Claims 1–5 of your Japanese application, your USPTO claims in the PPH request must each be limited to subject matter that falls within the scope of at least one of JPO Claims 1–5. A US independent claim that covers technology not claimed in any JPO-allowed claim is broader than the allowed claims and fails the correspondence requirement — that claim must be excluded from or narrowed in the PPH request. How to show correspondence: you prepare a 'claim correspondence table' — a two-column table with: Column 1: OLE claim number (your USPTO claim number); Column 2: corresponding OEE claim number(s) (the JPO-allowed claim number the USPTO claim corresponds to). For dependent claims: if a dependent claim's independent base claim corresponds to an OEE allowed claim, the dependent claim typically also satisfies the correspondence requirement automatically. Narrowing claims for correspondence: it is very common to need to amend OLE claims to bring them within the scope of the OEE allowed claims. This is expected and legitimate — the PPH request documents the amendment. IMPORTANT: narrowing claims for PPH correspondence creates prosecution history that might establish estoppel for the doctrine of equivalents in US courts. Consider whether any narrowing amendments you make for PPH correspondence might limit your infringement assertions. This is an important strategic consideration — if the narrowed scope is commercially sufficient, PPH is clearly worth it; if the narrowing significantly limits coverage of your commercial embodiment, weigh the time savings against the scope sacrifice.

PPH typically achieves dramatically faster first Office Actions and allowances compared to standard examination. Time comparisons at major patent offices: USPTO: standard first Office Action wait = 18–24 months (varies by technology art unit); PPH first Office Action = 2–6 months from PPH request filing. That is a 75–90% reduction in wait time. JPO (Japan): standard first OA = 10–16 months from examination request; JPO PPH = 2–4 months. KIPO (Korea): standard first OA = 8–12 months from examination request; KIPO PPH = 1–3 months. IP Australia: standard FER = 12–18 months from examination request; PPH = 3–6 months. EPO: standard first communication = 18–30 months from filing (or examination request); PPH = not officially measured but typically faster. Cost savings from PPH: the primary cost savings are indirect. By compressing the prosecution timeline, PPH reduces: (1) attorney time for status monitoring; (2) maintenance fees paid during prosecution (a patent that issues 2 years earlier avoids 2 years of pre-grant attorney fees); (3) foreign attorney fees in each country (foreign prosecution is expensive — faster resolution at each office means fewer billing cycles); (4) the commercial risk from having patent applications pending rather than granted (granted patents have stronger negotiating value). Allowance rate impact: PPH applications tend to have significantly higher allowance rates at the OLE than standard applications. This is partly because applicants often file stronger, cleaner claims at the OLE based on the OEE's search results, and partly because the OEE's allowed claims provide meaningful guidance to the OLE examiner.

PCT-PPH is a specific type of PPH that uses the Written Opinion of the International Searching Authority (WO-ISA) or the International Preliminary Report on Patentability (IPRP) from a PCT application as the basis for a PPH request at the national/regional stage — without needing a prior allowance from a foreign national patent office. This is how it works: (1) You file a PCT application; (2) The PCT application is searched and examined by an International Searching Authority (ISA) — for example, the USPTO, EPO, JPO, KIPO, or IP Australia, depending on which ISA you selected; (3) The ISA issues a Written Opinion (WO-ISA) indicating which claims are novel, inventive, and industrially applicable (eligible for PCT-PPH = at least one claim positively assessed); (4) At national phase entry (31-month deadline), you file corresponding claims at each participating national office; (5) You file PCT-PPH requests at each national office using the positive WO-ISA or IPRP as the basis. Why PCT-PPH is powerful: it allows you to leverage ONE PCT examination at ONE ISA to fast-track examination at MULTIPLE national offices simultaneously. You don't need to wait for a national allowance at one office to use as the basis at another — the PCT examination serves as the OEE for all PCT-PPH offices. Cost consideration: PCT-PPH typically carries no additional government fee at participating offices. The only cost is attorney preparation time for the claim correspondence tables and PPH request documents at each national office. Common strategy: file PCT → select USPTO or EPO as ISA (well-respected ISAs whose positive opinions are accepted broadly) → get positive WO-ISA → enter national phase → file PCT-PPH simultaneously at USPTO, JPO, KIPO, IP Australia, and other offices → receive fast-track examination at all offices simultaneously, often getting grants from multiple offices within 12–18 months of PCT national phase entry. Difference from regular PPH: regular PPH requires waiting for a national allowance from one specific OEE; PCT-PPH uses the PCT Written Opinion immediately at national phase entry without waiting for any national allowance.