Which PCT International Search Authority (ISA) should I use?

Below is a reexamination of a popular article from 2013, Which PCT International Search Authority (ISA) should I use? Originally published by Jeff Shieh, we update the statistics for 2016 and take a look back at the processes involved in selecting a PCT International Search Authority:

The International Search Report (“ISR”) is a fundamental part of the PCT procedure. Once a PCT application is filed, an International Search Authority (ISA) performs a search of the prior art, and provides the results to the applicant in the form of an ISR. The applicant can use the ISR to gain an insight into what prior art they might encounter during examination after national phase entry.

An ISA is, in effect, a patent office with its PCT hat on. Most ISA searchers and examiners are simply examiners at their local patent office, with special training in the special requirements of the PCT (note: the USPTO outsources some of its PCT International Searches to private search companies).

There are presently 20 ISAs, up from 15 in 2013. Every Receiving Office allows applicants access to at least one ISA. Some countries allow PCT applicants to choose from more than one ISA.

The choice for most applicants worldwide is their local patent office, if it’s available as an ISA. Even when there’s a choice of ISAs, there seems to be a default choice to stick with the local patent office. Many applicants will ultimately want to enter the national phase in their local country, so having the search performed by someone with experience in that country (i.e., a local examiner) may be useful.

However, if you have the option of choosing from more than one ISA, it’s worth taking some time to think about the advantages and disadvantages of the different options.

The US, in particular, offers a wide range of ISAs to applicants for which it acts as receiving office. The available ISAs for US-filed PCT applications are:

  •  IP Australia (Australian Patent Office)
  • European Patent Office (EPO)
  • Korean Intellectual Property Office (KIPO)
  • Rospatent (Russian Patent Office)
  • United States Patent and Trademark Office (USPTO)

So which factors might you want to consider when choosing which ISA will search your PCT application?

1. Cost

ISAs are free to set their own fees. The EPO as ISA, for example, has the highest search fee of US$2,143 (as of April 1, 2016). The USPTO charges US$2,080. KIPO charges only $1,117, whereas the Russian Federal Service for IP charges an amazing $430 (no, there isn’t a missing digit!) If cost is critical, Rospatent or KIPO offer savings of around $1,000-2,000 over the USPTO and EPO options.

2. Quality

This is where things get interesting. As mentioned above, one of the major advantages of the PCT is the ISR, which, while not binding on other patent offices, at least gives an indication of the prior art that might be faced in the national/regional phase.

The feedback we had from our 2015 Global Patent & IP Trends Indicator (get a copy here) tells us that US applicants consistently found Korea to be the fastest and great quality search authority. Many praised the high speed of the search, and there were many more positive comments about quality compared to other ISAs. “We like Korea for cost, speed, clarity”, “Good value and speed with South Korea search authority”, “Excellent. Liked the quality of the search report and the time it took.”

Next for quality (or possibly even tied for first depending on how you look at it) was the EPO. Respondents made comments like: “EPO has been prompt and thorough”, “EPO is best in terms of quality”, “More comprehensive and quicker than USPTO” and “the European search authorities are of a much better quality”. The adulation wasn’t universal. One respondent said “EPO speed is good, but cost is high” while one contradicted and noted that “speed is slow, occasionally non-competent examiner”. Many criticized these delays (although the same complaints were made occasionally about every ISR).

The USPTO comes next on the quality scale, followed by Rospatent. Both received positive and negative comments about quality. The USPTO was regularly measured against the EPO and found lacking (that specific comparison is probably a source of many of the negatives). While there weren’t enough answers to be sure, Rospatent seemed to be judged more in terms of its status as an extremely low cost option. It may therefore be that Rospatent is clearly poorer than the USPTO, but people don’t expect as much of Rospatent, so they tend to boost its rating somewhat to account for this. There were a couple of comments about Rospatent being very slow and inadequate. This may be in specific subject matter areas, or perhaps there’s a lot of variance across cases.

We didn’t receive enough feedback about Australia to make a meaningful assessment; however, some people noted they were “about average”.

3. Speed

Comments consistently suggest that KIPO offers a very fast search. There were very mixed comments about speed from Rospatent – you might get lucky and get a really fast search, or you could be waiting a very long time indeed. Most comments about the EPO’s speed were fairly positive (or at least compared it favorably with the USPTO’s speed). More than one respondent mentioned apparent improvements in speed from both the EPO and the USPTO over the last year or so. Again, we didn’t get enough feedback about Australia to draw any meaningful conclusions.


Cost, quality and speed can all be measured directly, but there are other factors to consider.


It’s fairly common for US applicants to file a US application in parallel with a PCT application. Many applicants who do this choose to have the EPO do the PCT search, because they like receiving a second opinion to complement that of the US examiner.

Easing Passage Through the EPO

Related to diversity, we were also told that many applicants choose the EPO because it gives an excellent view into how the application will be examined if the application enters the regional phase in Europe. In general, the same examiner that did the ISR will also be assigned to the case for European examination. While there’s no guarantee you’ll get the same examiner, or that they won’t change their mind later (perhaps if they find new art during a top-up search) the odds are good that you’ll face the same prior art and arguments once you enter the regional phase in Europe. You also get a modest reduction in official fees at regional phase entry into Europe if the EPO prepared the ISR.

Subject Matter

Note that not all ISAs will search all subject matter. A classic issue is business methods and pure software claims, which the EPO will simply refuse to search. KIPO, on the other hand, will search all subject matter that the USPTO searches.


The issues are too complex to recommend a single ISA for all situations, or to suggest one ISA is the “winner”. A few general points did come through loud and clear though:

  • It’s a toss up for the best search (on average). KIPO might be overtaking the EPO in terms of speed and quality of search compared to three years ago, especially when you look at the price differential. If you want a very good search and save a thousand dollars in the process, KIPO may be your best choice.
  • If money is really tight and you simply have to save every last dollar, consider Rospatent but don’t be surprised at a prolonged wait time.
  • All of which leaves the poor old USPTO without a specific category. It actually doesn’t measure up too badly overall, but KIPO seems to be considered as good at half the price, the EPO is better, Rospatent is cheaper and Australia is average.

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