How does MPEP address the obviousness of similar proportions or amounts?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

The MPEP addresses the obviousness of similar proportions or amounts in section 2144.05. According to this guidance:

“Generally, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical.”

This principle suggests that:

• Similar proportions or amounts are generally considered obvious
• Mere changes in proportion or concentration are typically not patentable
• To overcome obviousness, the applicant must show that the specific proportion or amount is critical or produces unexpected results

The MPEP further elaborates that this principle applies not only to concentrations and temperatures but also to other variables such as time and pressure. However, it’s important to note that each case must be evaluated on its own merits, considering the specific facts and circumstances of the invention and the prior art.