ln> how long does it take for approval / next step?

The U.S. Patent Office will treat any non-provisional patent application as confidential until the patent application is published.

This usually happens 18 months after filing the application. It would be reasonable to think that the examination process should only take a couple of months, but the truth is that the patent office has quite a backlog of pending patents and the process could take quite a long time.

The Office of Initial Patent Examination usually reviews the applications fairly quickly, but once the application is assigned to an examiner it could take years for the application to be examined. Some take less time than others, but biomedical, electrical and business method related units take the longest.

A patent attorney, agent, or the inventor himself may get information on the status of the application from the patent office if requested during this confidential period, but typically no one else can.

Once the patent application is published, it is available to the public and no longer confidential.

Ongoing status updates are trackable here.

For this patent (pending), these are the events so far.