Selecting Patents for the RFID Patent Data Base
Basic approach
The patent search consisted of three major steps.
- A keyword search was run using the U S Patent Office advanced search service using the keyword “RFID”. This created a preliminary list of 978 “potential” patents.
- As the potential patents were reviewed, additional keywords were found and added to the keyword list.
- A number of patents were selected for detailed analysis. Each of these patents contained a list of reference patents. These reference patents were added to the potential list. During analysis, additional keywords were also found. These new keywords were added to the keyword list and the 3 step process was repeated.
This process produced a final list of 4279 potential patents. In the process of producing this report, every one of those patents was accessed in some form or another.
Did this search COMPREHENSIVELY find all the patents related to RFID? In strict terms, no. Every technology can be referred to using multiple terms. For example, radio frequency communication is also referred to as contactless data transmission or non-contact data transmission. Cross reference and classification materials were used to help in this regard, but they, themselves, are not comprehensive.
Once the technical focus moves only slightly, a new set of terminology enters the picture. For example, every RFID tag has an antenna. To be comprehensive, do we need to include all antenna patents? Antennas can be made of many materials, including copper. To be comprehensive, do we need to include all patents for improvements to copper? Achieving a result that can be called “comprehensive” would end up including a huge number of patents, most of which are only remotely related to the main subject.
Was the search THOROUGH? Yes, on the basis of extension. A search for the keyword “RFID” alone would not have been adequate. Once the patents found in that search are used as a reference to other patents, however, we essentially incorporate the knowledge and effort of additional people in the process, most of whom we can expect are trained in the art. This includes patent attorneys, professional patent searchers and the U.S. patent office examiners themselves.
Was the search ADEQUATE? This is always dependent on the intended application. For many users of this report, it will be adequate, especially on a cost - benefit basis. Where it is not adequate, the report will, again, provide a very cost – effective basis to extend the search.
Keywords
The following list shows all the keywords which were eventually used to search for patents. The keyword search was run against the entire text of the patents, which includes title, abstract, patent keywords, claims and description. The number shown with the keyword or keyword phrase is the number of patents found for that keyword or phrase.
The keyword phrases shown in the list were specified as phrases. For example, Electronic Identification Device was specified as “ Electronic Identification Device”. Where the keywords were searched for independently, the search string is shown.
Again, the patent count is only for U.S. patents.
xxx....................................................................................................................436
Electronic Identification Device................................................................... 66
xxxxxxxxxx.......................................................................................................... 35
Inductive xxxxx................................................................................................. 10
Inductive xxxx..................................................................................................... 8
Parasitic xxxx......................................................................................................4
Passive AND xxxxxx AND xxxxxx............................................................... 2212
Passive xxxxx....................................................................................................41
Remote xxxxxxxxxx............................................................................................39
Remote xxxxxx.................................................................................................166
RFxxxxxxxx......................................................................................................... 88
RFID................................................................................................................ 978
As an aside, the keyword RFID is not unique to Radio Frequency Identification. Another significant use of this acronym is for Radio Flow Labels. These are level 2 internet protocol codes used with wireless systems to identify radio broadcast data packets.
Prescreening
The goal of the search process was to create a composite list of patents that represents a true picture of the extent to which RFID is being protected by patents and the depth to which the technology is covered. In gathering this list, especially in the referenced patents, the patent subjects get quite broad. One way to reduce the size of the list is to “prescreen” the list according to some simple criterion.
For this report, there was very little prescreening done. The two prescreening criterion used were:
· The patent had to be a U.S. patent. Foreign patent references, of which there were many, were excluded.
· The patent had to be a utility patent. Design patents were excluded.
Why was the prescreening not deeper? Here is an example patent title: DNA encoding neospora dihydrofolate reductase-thymidylate synthase (this is a true title). It probably doesn’t have much to do with RFID. This particular patent was not screened out. The reason is our attempt to try to support a pretty likely use of the report information.
One typical use of the report will be to reduce patent search costs. Even though this biotech title does not qualify as RFID, the patent with that title was directly referenced by another patent that has an RFID related keyword in it. So someone doing an RFID related keyword search will turn up the RFID patent that shows the biotech patent as a reference. But, in the patent documents, referenced patents are only listed by number, date and inventor. To determine if a referenced patent is valid, additional searching is needed. At a few hundred dollars an hour, this cost can run up pretty fast. For anyone searching RFID, the data provided in this report can quickly and very cost effectively screen such patents out, but only if the entire chain is included.
