October Term 2013 · Docket 13-369

Does a patent claim lack definiteness if it allows two reasonable readings?

The parties dispute whether a patent claim is definite when it permits two reasonable interpretations of its scope.

Official caption
Nautilus, Inc. v. Biosig Instruments, Inc.
Latest argument session
Latest official Court activity
Latest verified event
Argued
Sources analyzed through
Official Transcript

Verified source milestones

  1. — An official oral-argument transcript was verified.
  2. — An official oral-argument transcript was verified.

The arguments, in order

This case may have been argued more than once. Each entry below uses that session's official transcript. Later arguments do not erase earlier ones.

  1. Argument 1 ·

    What happened at the argument

    Nautilus contends the claim is not particular and distinct. It argues the claim is ambiguous after applying all interpretive tools.

    Biosig contends the Federal Circuit correctly applied the definiteness test. It argues the claim provides reasonable notice of the invention's boundaries.

    questions_and_answers

    Read the official transcript for this argument · Official argument details

    Sources used for this argument breakdown

A citizen's guide to the whole case

What this case is about

This case concerns a patent for a heart-rate monitor. The core issue is the legal standard for patent claim definiteness. One side argues the claim is ambiguous because it allows two reasonable readings. The other side argues the claim is definite because a skilled artisan understands its scope.

Official sources for this section

How the case got here

The Supreme Court heard oral argument in this case on April 28, 2014.

Official sources for this section

What each side wants

Nautilus wants the court to reverse the lower court decision. It seeks a ruling that the patent claim is ambiguous and invalid.

Biosig wants the court to affirm the lower court decision. It seeks a ruling that the patent claim is definite and valid.

Official sources for this section

What each side says

Nautilus argues the claim is ambiguous because it has two reasonable readings with different scopes.

Biosig argues the claim is definite because it gives a skilled artisan reasonable notice of the invention's boundaries.

Official sources for this section

What the justices asked

Justice Sotomayor asked about the purpose of the invention if it only covered spacing without canceling EMG.

Justice Scalia asked about the limits on trial and error in determining electrode spacing for a patent claim.

Official sources for this section

Why it matters

The outcome defines the legal standard for patent claim definiteness. It determines whether ambiguous claims remain enforceable. This affects patent holders and competitors in the technology sector.

Official sources for this section

What happens next

This article currently covers the argument record. Use the official docket link for later case activity.

Official sources for this section

Official Court provenance

Official docket and case history · Official Supreme Court oral-argument detail page

Title and summary sources

Revision history

  1. Revision 1 · Official Transcript ·

    Correction: Rewritten to the concise citizen-facing editorial standard.

  2. Revision 2 · Official Transcript ·

    Correction: Migrated to the dated official Court activity contract without model use.

Download this sanitized case as JSON