Microsoft Corporation v. Sandpiper CDN, LLC

IPR2026-00174

Microsoft seeks Director Review of a PTAB institution decision that ordered review of an expired content‑delivery patent owned by Sandpiper CDN. The petition argues the Board misapplied settled‑expectations doctrine and misread the district‑court record, making the decision an outlier.

Jurisdiction
US PTAB
Case Number
IPR2026-00174
Decision Date
17 December 2025
Filing Date
17 December 2025

Detailed Summary

In a Request for Director Review, Microsoft challenges the PTAB’s decision to institute inter partes review of Sandpiper CDN’s U.S. Patent No. 8,478,903, which covers alias‑name mapping in content delivery networks. The petitioner argues that the Board improperly applied the settled‑expectations doctrine to an expired patent, mischaracterized a brief district‑court procedural pause as a stay, and relied on a single prior‑art reference (Kenner) that does not disclose critical claim limitations. Citing numerous prior decisions where expired patents were denied review, Microsoft contends the institution decision is inconsistent and arbitrary, and urges the Director to reverse it.

Practitioner Note

This case demonstrates the evidentiary and procedural standards applied in patent matters before local courts. Understanding the court's reasoning in Microsoft Corporation vs Sandpiper CDN, LLC is valuable context for structuring arguments or assessing risk in similar proceedings.

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Disclaimer: This page contains an automated summary based on publicly available judicial records. The content is generated for informational purposes only and does not constitute legal advice. Always verify details against the original source judgment before relying on this information for any legal purpose. If you believe any information is inaccurate, please contact us.

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