Drafting a patent application is both an art and a science. One debate that often arises is how much of the invention's environment needs to be included in the figures and specification. There are many factors that come into play in making this decision, including the nationality of the patent filing, the strategic purpose of the filing, etc. Some argue that extra disclosure detracts from the invention and limits the ultimate scope of the invention. Others say that extra disclosure can sometimes be crucial to avoid prior art that was unexpected, or to avoid an unreasonably broad interpretation by an examiner or PTAB judge at the USPTO.

One classic trick that illustrates the possible advantage of extra disclosure in a patent application (even disclosure of mundane, and seemingly non-inventive and irrelevant details) is to turn the tables on an examiner.  For example, when an examiner knowingly cites an element in the prior art that is something different than the claim intended (e.g., using BRI), the ability to add the equivalent element to the claims blocks the examiner. However, one can only add the actual equivalent element if it is described in the specification and figures.

Consider an example where an examiner cites a control signal for a device as showing a sensor for sensing operation of that device. The examiner may argue that the control signal could be used as a way to know what is happening with the device, and it therefore a sensor. If the specification included disclosure of the control signal and a sensor in combination, then the claims can be amended to include the control signal and sensor together, and thus force the examiner's hand. This is helpful even if the control signal aspect is not at all inventive or even related to the sensor aspect of the invention that was originally claimed.