Patent searches have also evolved significantly over time. For instance, patent lawyers once spent several days combing through huge volumes of printed material in patent libraries, looking for the crucial piece of prior art. Next came databases on a national level, followed by globally available databases such as Espacenet, Google Patents, and databases provided by the World Intellectual Property Organization (WIPO). Suddenly, it became possible to do a patent search from anywhere while sitting at one's desk and typing keywords and classification numbers into a search engine.
Nonetheless, even with all the modern possibilities offered by these searchable patent databases, the search process was far from being fully automated, and the user had to rely not only on the use of the appropriate keywords but also on Boolean expressions and personal experience. The technological boom, electronic filing and publications, and international cooperation led to an unprecedented explosion in
