Once upon a time I studied thermodynamics. I was told that the first time you study thermodynamics you don't know what you are doing; the second time you think you know what you are doing; and the third time you know you don't know what you are doing, but by that time it's too late so you just get on and do it. Patent searching is a bit like thermodynamics in that respect. It may seem difficult at first and then appear easier, but a little confidence can be a dangerous thing. There is more to patent searching than entering a few keywords and numbers.
Your intentions define what type of search you need to do. If you have an idea for a product that you want to protect then a novelty or patentability search is required. If you want to import a product into a country or start using a new product then a freedom-to-operate search is required. These two types of searches have vastly different requirements. Freedom-to-operate searches are relevant to a specific country you want to operate in, are limited to current patents and involve investigating every feature of the product. Novelty searches need to be worldwide, back as far in time as possible, with a view to the product as a whole. With over 30 million patents worldwide and a million or so being filed every year that's a lot of searching, which leads me to...
The International Patent Classification. The International Patent Classification, or IPC, is a classification system used to classify patent applications into technical groups. There are currently over 70,000 groups with more being added as it is developed and new technologies emerge. The IPC, and other similar classification systems, help with searching as it enables you to search in an area where similar ideas to your own will be found. This helps reduce the total number of patents you need to look at, and is widely considered to be the best starting point for a search. Often more than one group needs to be searched because each group focuses on a different aspect of the invention, and a patent is classified according to how it has been described.
Similar ideas can be described in a multitude of ways due to the variety and complexity of the English language, not to mention all of the other languages patents can be filed in. The World Intellectual Property Organisation or WIPO has ten official filing languages including Arabic, Chinese, French, German, Japanese, Korean, Portuguese, Russian and Spanish as well as English. It is no defence to claim ignorance of a relevant patent just because it was filed in a language you couldn't read. Forget about the foreign language problem for a moment and consider English again. You may describe your idea using certain well known words, but another inventor could describe a similar idea in equally well known words. For example consider "plastic" vs. "polyethylene", or "metal" vs. "copper", or "fan" vs. "air movement device". You need to be able to think laterally to determine a range of relevant keywords, including generic ones such as plastic and metal, that will be useful in your searching, but also be able to recognise a further keyword in a specification as being relevant to you. In my primary field of pharmaceuticals I have to consider and locate references not only to the name of the drug (Citalopram), but to the name on the box it comes in (Cipramil), its chemical name (1-[3-(dimethylamino)propyl]-1-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-carbonitrile), and what it is (an antidepressant), as well as a few other things. This is a complex example but all searches have to follow similar lines.
Patent searching is something anybody can do, and it can be done for free using national patent office databases or Google Patents or similar, but there are inherent limitations in all aspects of the process. Free databases don't often cover everything so you'll need to search more than one, and they all use different interfaces and codes. Many years of experience in a technical field doesn't always equate with being able to perform an adequate patent search. An expert patent search should be seen as a form of insurance or risk minimisation. The downside of not searching can be considerable, for example, significant patent filing costs can be thrown away if your new idea isn't so new, or worse, there is the possibility of being sued for infringement.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.
