Once a patent application has entered substantive examination procedure, patent examiners qualified in the field of technology concerned will check the patent documentation and ensure it complies with the patent laws. The most important step is to determine, as far as possible, whether or not the invention really is novel and inventive (non-obvious). Examiners do this by searching through databases of existing published patents and professional journal articles. If they find something they believe "anticipates" the invention concerned, they notify the applicants or their patent attorneys. This notification is sent out in the form of an "official action".