Finding and using patents for a bibliographical search

Patents are a valuable source of scientific information as well as business intelligence. In the case of the pharmaceutical industry, they provide early insights in a company's research programs and potential drug candidates. However, data contained in patents is often partial, biased and lacks the general objectiveness and perspective of peer-reviewed articles.
This laid the ground for Expert Opinion on Therapeutic Patents, which proposes critical reviews and analyses of patents (and articles) claiming the discovery of therapeutic compounds.

While authors have no problem at all compiling articles and data from the scientific literature, searching for patents often proves a hurdle. Here is an attempt at helping. A selection of databases and interfaces are briefly described.

Very much like for conventional scientific literature, several web-based interfaces propose search functionalities and access to patent databases. They are available to anyone and there is no need to be an IP professional to understand them. They may be free or require subscription. Search engines vary and it is recommended to read the instructions. However, they usually are obvious and easy enough to use, being not that different from Pubmed or Web of Science for example.
As ever, the selection of keywords is key to a successful search. Try several related or synonymous keywords. Also check if the search engine supports wildcard or truncated searches. The wildcard characters usually are *, ? and #. Boolean combinations and restricting searches to titles or abstracts can be necessary when a search returns too many irrelevant results.
In medicinal chemistry, searching for the molecular target is probably the best bet.

Researchers with access to SciFinder, Thomson Patents or Delphion for example will find these resources useful. Others can try:

• European Patent Office, which contains applications from most countries. You can save searches and save most original PDF files through the 'Save Full Document' link in the 'Original Document' tab.
  
• US Patent and Trademark Office, for US patents (an image can be downloaded)
• World Intellectual Property Organization proposes international patents applications. PDF and zipped TIFF images can be downloaded.
  
• Free Patents Online, for US, EU and some Japanese patents, as well as documents from the WIPO database. Powerful search engine (including a chemical search option) and access to the PDF files upon free registration.
• Google Patents, PDF available.

Patents filed in some countries, such as New Zealand and South Korea, are only accessible via their national patent offices (cf. links). However, chances are that these patents are also filed as WIPO patents.

I hope this demystifies patent searches.