How do time and expense factor into the assessment of undue experimentation?

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.

Time and expense are considerations in assessing undue experimentation, but they are not determinative factors on their own. The MPEP provides guidance on this in section 2164.06:

“Time and expense are merely factors in this consideration and are not the controlling factors.”

Key points to consider:

• Extensive time or high costs don’t automatically make experimentation “undue”
• These factors must be considered in context with other Wands factors
• The reasonableness of time and expense depends on the nature of the invention and the field of technology
• What’s considered reasonable can vary significantly between different technologies

For example, the MPEP notes a case where experimentation requiring 1-2 man-years was considered “clearly unreasonable,” while in another case, a $50,000 cost and 6-12 months of work was not considered undue experimentation on its own.