USPTO has just introduced a new database called PAIR (Patent Application Information Retrieval) which tracks the status of a public patent application. Here’s a blurb from the USPTO’s press release:
For the first time, anyone with Internet access anywhere in the world can use USPTO’s Web site (www.uspto.gov) to track the status of a public patent application as it moves from publication to final disposition, and review documents in the official application file, including all decisions made by patent examiners and their reasons for making them.
The system, known as Public PAIR (patent application and information retrieval), offers the public an advanced electronic portal to PDF viewing, downloading and printing an array of information and documents for approximately 500,000 patent applications not covered by confidentiality laws. As new applications become eligible for publication 18 months after they are filed, they will be added to the database. It is expected that about 300,000 application files will be added annually.
Source: ResourceShelf