Reasons a Preliminary Patent Search is Not Exhaustive of All Patents
This is referred as a preliminary search because the search, while helpful is not exhaustive. Why?
The first question is what is searched. And, the answer to that is that we are searching the prior art. Prior art is the term given to information (patents, periodical articles, newspaper articles, brochures, actual goods) that has been publicly disclosed prior to the filing date of the patent. It is this entire body of work that forms the backdrop of the analysis of novelty and non-obviousness of an invention.
Essentially prior art answers the question of what was already invented prior to the invention that has been submitted or the invention that has been discovered. Has the invention already been invented by someone else in the world? Is the invention, while new to the inventor, actually something that was invented many years ago by someone else? The answer to this question is found in the prior art. That is, if reliable and acceptable documentation can be found that someone else in the world already invented the invention, then the invention is not entitled to a patent.
Consequently, prior art encompasses everything that came before. Prior art is not limited to other United States patents, but includes virtually any publicly available information including patents and published patent application from any country in the world, academic papers and publications, trade and specialty journals and magazines, on line resources, brochures, sales material, and actual physical specimens. Such prior art can be in any language, and does not have borders.
Because that is a large volume of material, and as cost is always a consideration, a preliminary search can be done in a cost effective manner which provides a good initial view of the scope and content of prior art.
A preliminary search typically searches issued United States patents, published United States patent applications, and publication and/or Internet based searches. In other instances, these can likewise include worldwide on-line patent searches, which databases can include over 40 million patent references.
Once the proper scope and databases are selected for searching, the question then is how is a search conducted. There are two different strategies when searching. The first is searching based on patent classification. The US had a classification system for many years, and there is also an International classification system. The US has moved to utilizing the unified International classification system. And, the classification system is quite robust and can efficiently guide a searcher to relevant patents to search for an invention. In addition to the classification system, a searcher can search keywords that are associated with features of the invention. Additionally, a searcher can use a combination of keyword searching and classification searching. It can be difficult to rely on keywords alone, as patent law firms have a large vocabulary of synonyms, and, with so many different ways to describe the same thing, references can easily be missed by relying solely on keywords.
Cost. Cost is always an object. A full search of all patent offices, all libraries and all universities, as well as all on-line sources is obviously cost prohibitive. It is difficult to even quantify how much such a search would cost, as well as the sheer volume of manpower. There is a balance between cost and the quality of a search (i.e., there is a level of searching that provides a good cross-section of prior art and that is reasonable as far as cost). A preliminary search typically strikes the appropriate balance when it comes to cost/benefit analysis. A quality preliminary search with analysis by a patent attorney costs approximately $2000 to $3500.
Therefore, while a preliminary patent search is often very helpful, it is important to understand the limitations of any search and results of such search so that you can make an informed decision as to patent searching. Additionally, in some instances, searching may not be worth the cost. For example, in the software arts, it is often difficult to obtain a quality preliminary search, due to the types of references, the analogous nature of software, and the volume of information on the Internet regarding unpatented software.