How does the Halliburton case impact functional claim language?

The Halliburton case (Halliburton Oil Well Cementing Co. v. Walker, 329 U.S. 1 (1946)) significantly impacts the interpretation of functional claim language in patent law. Key points include:

• The case initially prohibited the use of functional language at the exact point of novelty
• This strict prohibition was later modified by Congress in 35 U.S.C. 112(f)
• Functional language is now allowed, but with specific interpretations

As noted in MPEP 2173.05(g): “Notwithstanding the permissible instances, the use of functional language in a claim may fail ‘to provide a clear-cut indication of the scope of the subject matter embraced by the claim’ and thus be indefinite.” This statement reflects the ongoing need to balance functional language with claim clarity, even after the Halliburton case’s impact was moderated by statutory changes.

To learn more:

• Halliburton case
• functional language
• patent claims
• MPEP 2173.05(g)