Background
Rembrandt Diagnostics, LP holds patents related to diagnostic testing equipment — the kind of portable analyzers used for rapid medical testing. Alere, Inc., a medical diagnostics company, filed an inter partes review (IPR) petition challenging Rembrandt’s patent at the Patent Trial and Appeal Board (PTAB), arguing that the patent’s claims were obvious over combinations of prior art references. In its original petition, Alere argued that a skilled artisan would be motivated to combine the prior art references in part for reasons of efficiency.
In its reply brief — filed after Rembrandt responded to the petition — Alere submitted an additional expert declaration and expanded its motivation-to-combine argument to specifically address cost and time savings as reasons to combine the references. Rembrandt objected that these arguments were impermissibly new — raised for the first time in the reply, when Rembrandt had no opportunity to respond. The PTAB rejected the objection and found the claims unpatentable as obvious. Rembrandt appealed, renewing its argument that Alere’s reply arguments violated the prohibition on new theories in IPR replies.
The Court’s Holding
The Federal Circuit affirmed on both grounds. First, the court held that Alere’s cost and time savings arguments in the reply were not impermissibly new. Under the PTAB’s IPR rules, a petitioner’s reply may respond to arguments made in the patent owner’s opposition, and may expand or elaborate on arguments raised in the original petition. The court found that the efficiency rationale was raised in Alere’s petition, and that the cost and time savings argument was a fair extension of that same rationale — it was a more specific articulation of efficiency, not a wholly new theory. A reply expanding on an argument that was fairly raised in the petition does not become a new argument simply because it adds detail or responds to the patent owner’s counterarguments.
Second, the court held that Rembrandt had waived its objection to allegedly new theories by making only a general objection — stating that Alere had raised new theories without identifying which specific theories were new or why they were impermissible. To preserve a new-theories objection, a patent owner must specifically identify the allegedly new arguments; a blanket objection is insufficient and will not preserve the challenge for appeal.
Key Takeaways
- An IPR petitioner’s reply may expand on and provide additional evidence for motivation-to-combine arguments raised in the original petition — elaborating on an efficiency rationale to specifically address cost and time savings is not a “new theory” if efficiency was already in the petition.
- A reply argument is impermissible only if it introduces a genuinely new legal theory or relies on evidence that is not responsive to the patent owner’s opposition; not every new detail or additional support crosses that line.
- Patent owners must make specific, targeted objections to allegedly new reply arguments — a general complaint that “reply introduces new theories” is insufficient to preserve the objection on appeal.
- PTAB practitioners on the patent-owner side should carefully review petitioner reply briefs and identify with specificity, in their sur-replies or at oral argument, exactly which statements they claim are new and why.
Why It Matters
Rembrandt Diagnostics v. Alere provides practical guidance on one of the most contested procedural issues in IPR practice: the permissible scope of petitioner reply briefs. Patent owners frequently object that petitioners use reply briefs to introduce new arguments that the patent owner never had the opportunity to address. This decision reinforces that the key distinction is between (1) elaborating or expanding on arguments already in the petition, which is permissible, and (2) introducing wholly new legal theories or factual bases, which is not. The ruling also highlights a critical procedural trap: patent owners who fail to specifically identify the allegedly improper new arguments risk waiving the objection entirely, undermining their ability to challenge the PTAB’s reliance on those arguments on appeal.
For IPR practitioners, the case provides a road map for both petitioners (who can expand efficiency-based motivation arguments in replies) and patent owners (who must specifically object to new theories rather than making boilerplate objections). In the competitive world of PTAB litigation, procedural precision is as important as substantive strength.