Sandpiper CDN, LLC v. Microsoft Corp.

Sandpiper CDN, LLC, a recently formed Delaware entity, has initiated patent infringement litigation against Microsoft Corp. in the Eastern District of Texas. Sandpiper CDN operates as a Patent Assertion Entity (PAE), having acquired a portfolio of content delivery network (CDN) patents from Level 3 Communications (which later became Lumen Technologies). The original Sandpiper Networks pioneered commercial CDN technology in the 1990s. Microsoft, a global technology conglomerate, is accused of infringing these patents through its Azure platform, specifically its "content delivery infrastructure and services," including Azure CDN Standard from Microsoft, Azure CDN Standard from Edgio, Azure CDN Premium from Edgio, and Azure Front Door Standard and Premium.

The sole patent asserted in this case, according to the provided metadata, is U.S. Patent No. 8,478,903, titled "Shared content delivery infrastructure." This patent generally describes methods for servers in a computer network to off-load requests for specific resources by dynamically determining and utilizing a different server, or "repeater," to process those requests, thereby facilitating the efficient replication and delivery of content in computer networks. The lawsuit is before Judge Rodney Gilstrap in the Eastern District of Texas, a venue historically favored by patent plaintiffs due to its reputation for a "rocket docket" with fast adjudication times and plaintiff-friendly verdicts, although recent Supreme Court rulings have aimed to refine venue rules.

This case is notable as part of a broader assertion campaign by Sandpiper CDN against major players in the content delivery industry, including parallel lawsuits against Google and Comcast, targeting their respective CDN offerings. The '903 patent is also the subject of an ongoing Inter Partes Review (IPR2025-00969) filed by Google LLC at the Patent Trial and Appeal Board (PTAB), where Sandpiper CDN's motion for discretionary denial was rejected. This extensive litigation underscores the value and contested nature of foundational CDN technologies in the current digital landscape, where efficient content delivery is critical for cloud services and streaming media.

The case "Sandpiper CDN, LLC v. Microsoft Corp." (2:25-cv-664) was filed in the Eastern District of Texas. Sandpiper CDN, LLC asserts U.S. Patent No. 8,478,903, among other patents, against Microsoft, alleging infringement related to Microsoft's Azure platform and its content delivery infrastructure and services, including "Azure CDN Standard from Microsoft," "Azure CDN Standard from Edgio," "Azure CDN Premium from Edgio," and "Azure Front Door Standard and Premium".

Here's a chronological summary of the key legal developments:

• Initial Filing (2025-06-26): Sandpiper CDN, LLC filed its complaint against Microsoft Corporation in the Eastern District of Texas. This case is part of a broader campaign by Sandpiper CDN asserting patents formerly owned by Level 3 Communications.

• Parallel PTAB IPR Proceedings:

  • IPR2025-00969 (Google LLC v. Sandpiper CDN, LLC): U.S. Patent No. 8,478,903, also asserted in this case, is the subject of a pending IPR petition filed by Google LLC. On October 10, 2025, the Director denied Sandpiper CDN's motion for discretionary denial in this IPR.
  • IPR2026-00180 (Microsoft Corporation v. Sandpiper CDN, LLC): Microsoft Corporation filed an Inter Partes Review (IPR) petition (IPR2026-00180) against Sandpiper CDN, LLC, challenging U.S. Patent No. 10,701,173. The IPR petition was filed on December 24, 2025, and challenges claims 1-14 of the '173 patent. This IPR concerns a patent titled "Content Delivery Network Caching Methods," which describes a "late-binding" approach for CDN nodes to serve cached content. The grounds for unpatentability primarily involve obviousness over prior art like O'Rourke (Patent 7,912,921) and other references.

The case against Microsoft (2:25-cv-664) is currently pending in the Eastern District of Texas. The search results indicate that Sandpiper CDN has also filed similar lawsuits against other companies, including Comcast and Google, asserting the '903 patent in those actions as well. While there's information about the filing and related IPRs, details on subsequent pleadings (answer, counterclaims), substantive pre-trial motions (other than IPR-related stays/motions to dismiss in other cases), claim construction, discovery, or trial events specifically for this Microsoft case are not yet publicly available or detailed in the provided search results. Given the recent filing date (June 2025), the case is likely still in its early litigation stages.

I'll search for press coverage of this case from multiple angles.

The first searches surfaced docket and PTAB documents rather than press. Let me now target media outlets specifically.

Press coverage appears sparse. Let me probe more outlets and specific angles.

Press & media coverage

Bottom line: despite the case being a multi-defendant PAE campaign against household-name tech companies, I found no dedicated news article — mainstream or trade — about Sandpiper CDN v. Microsoft itself. Searching the caption, the parties, the patent numbers, and the parallel IPRs surfaced docket aggregators (CourtListener, RPX Empower, Docket Alarm) and primary filings, but not reporting. The closest thing to coverage is (a) subscription patent-market services, and (b) PTAB-focused practitioner commentary on the parallel IPRs covering the same patents. No outlet I found has reported a damages figure, verdict, or settlement in this case — the case remains pending with the willfulness dispute and IPR proceedings as the live fights.

The most substantive third-party item tied to the campaign is a short post from Unified Patents, published 2026-08-11, which describes Sandpiper CDN LLC as "an NPE" that "has sued several companies accusing content delivery networks (CDN) and related services," and states that Unified's team "is using Pearl to identify and chart prior art against patents owned by Sandpiper CDN LLC." That is a defensive-aggregator announcement rather than journalism, and it names no defendant. On the commercial-intelligence side, RPX Empower maintains a docket page for 2:25-cv-00664 showing a filing date of 06/26/2025 in the E.D. Tex., and RPX news items have tracked the campaign's other legs — including an item on the Level 3 → Sandpiper CDN assignment (RPX, 2024-06-28) and the Comcast suit (RPX). Those RPX pieces are paywalled; I found their titles and URLs through the citations in Sandpiper's own amended complaint (D.I. 41, ¶ 56 nn.34–36) rather than reading the articles themselves, so I cannot verify their contents beyond what the complaint quotes.

The one body of writing that discusses these patents in detail is patent-blog analysis of the PTAB side. The PTAB Litigation Blog (authored by Mike Lavine, and syndicated by Jones Day and Lexology) reported on 2026-09-04 that in Microsoft Corporation v. Sandpiper CDN, LLC, IPR2026-00180 (Paper 15, 2026-05-06), Director Squires denied Sandpiper's request for discretionary denial of Microsoft's IPR petition against the '173 patent, holding that only half of Microsoft's challenges rested on the previously considered O'Rourke reference while the rest relied on Middleton — a reference Sandpiper had not cited during prosecution despite it being commonly assigned to Sandpiper's predecessor, Level 3. The blog quoted Squires: "a patent applicant's failure to provide prior art that it owns cuts against its settled expectations and weighs against discretionary denial," and drew the practitioner takeaway that "partial overlap under § 325(d) may not be enough." That analysis is explicitly interpretive — it extracts lessons for PTAB practitioners and goes beyond what the Director's decision says doctrinally. Notably, this is a different IPR from the Google-led '903 proceeding discussed in the prior sections, and it reflects a pattern of Director-stage denials rather than any merits ruling.

Two additional cautions for anyone reading this section alongside the court record. First, the press-facing narrative in this litigation is coming from the plaintiff itself: Sandpiper's amended complaint pleads willfulness in part on the theory that Microsoft, "as a member of RPX," received litigation notices and thus knew of the patents — a theory Microsoft attacked as "a series of logical leaps built on media and third-party alerts, not on any alleged pre-suit notice to Microsoft" (Microsoft's motion to dismiss, D.I. 43 at 9, quoted in PTAB Exhibit 1039). That motion was ultimately denied — the court overruled Microsoft's objections and adopted Magistrate Judge Payne's recommendation on 2026-07-13 (govinfo, E.D. Tex. 2:25-cv-00664) — but that is a docket ruling, not press coverage. Second, a Law360 firm/attorney case listing for Fish & Richardson's Joseph R. Dorris shows "June 26, 2025 Sandpiper CDN, LLC v. Microsoft Corporation, Texas Eastern," which suggests Fish & Richardson is on the Microsoft side, though Law360's page is a data listing, not an article, and I could not independently confirm the scope of that firm's role from a press source.

One flag on the case metadata and prior sections: the metadata lists only U.S. Patent No. 8,478,903, and the case-overview section states the '903 is the "sole patent asserted." The operative second amended complaint asserts six patents — 8,478,903, 8,924,466, 9,456,053, 9,722,883, 9,762,692, and 10,701,173 (D.I. 41, Exhibits A–F; see also Microsoft's D.I. 43 briefing). The later "Key legal developments" section's "among other patents" phrasing is the accurate one. I also found a second, later Microsoft case, 2:26-cv-00681, filed 2026-08-11 in the E.D. Tex. (Ex Parte) — a development not reflected in the earlier sections, though I could not verify the patents at issue.

Sources

• January 26, 2026
• Microsoft incorporates by reference the invalidity claim charts and contentions served by and Comcast in the Sandpiper CDN, LLC ...
• Sandpiper CDN, LLC v. Microsoft Corporation, 2:25-cv-00664 - CourtListener.com - Sandpiper CDN, LLC v. Microsoft Corporation (2:25-cv-00664)
• IPR2026-00095, No. 1039 Exhibit - EX1039 Sandpiper CDN, LLC v Microsoft Corp, No 225 cv 00664, Dkt 43 ED Tex (P.T.A.B. Feb. 13, 2026) - Exhibits:
• Amended Complaint – #41 in Sandpiper CDN, LLC v. Microsoft Corporation (E.D. Tex., 2:25-cv-00664) – CourtListener.com - 8,478,903, because of Microsoft’s previous interest in acquiring a CDN, Microsoft having been
• UNITED STATES PATENT AND TRADEMARK OFFICE
• Complaint analysis | 2:25-cv-00664 | Sandpiper CDN LLC v. Microsoft Corp | Ex Parte
• Patent Litigation Intelligence
• IN THE UNITED STATES DISTRICT COURT FOR THE EASTERN DISTRICT OF TEXAS MARSHALL DIVISION
• The specification must describe the claimed invention in sufficient detail so that a POSITA can recognize what is claimed
• 48. Further, as detailed in Sandpiper's October 29, 2025 Response to Microsoft's Interrogatory No
• IN THE UNITED STATES DISTRICT COURT FOR THE EASTERN DISTRICT OF TEXAS MARSHALL DIVISION

Here is the counsel of record representing Sandpiper CDN, LLC in Sandpiper CDN, LLC v. Microsoft Corp., Case No. 2:25-cv-664 in the Eastern District of Texas:

Boies Schiller Flexner LLP

• Mark D. Schafer

  • Role: Likely lead counsel or a key member of the plaintiff's litigation team.
  • Firm Office Location: Washington, D.C.
  • Relevant Experience: Mark Schafer is a partner at Boies Schiller Flexner and co-chairs the firm's Intellectual Property practice. His experience includes a wide range of intellectual property litigation, including patent, trade secret, and copyright disputes, often involving complex technologies in federal district courts and the U.S. Court of Appeals for the Federal Circuit.

• Ryan D. Dykal

  • Role: Likely lead counsel or a key member of the plaintiff's litigation team.
  • Firm Office Location: Washington, D.C.
  • Relevant Experience: Ryan Dykal is a partner at Boies Schiller Flexner, focusing on high-stakes intellectual property and commercial litigation. He has represented both plaintiffs and defendants in patent infringement cases across various technologies.

• Philip Eckert

  • Role: Likely counsel.
  • Firm Office Location: Washington, D.C.
  • Relevant Experience: Philip Eckert is an attorney at Boies Schiller Flexner with experience in complex litigation, including patent disputes. He has appeared in filings for Sandpiper CDN, LLC in this case.

• Connor Coupe

  • Role: Likely counsel.
  • Firm Office Location: Washington, D.C.
  • Relevant Experience: Connor Coupe is an attorney at Boies Schiller Flexner who works on intellectual property and other complex commercial litigation matters.

• Carolyn E. Drell

  • Role: Likely counsel.
  • Firm Office Location: Washington, D.C.
  • Relevant Experience: Carolyn Drell is an attorney at Boies Schiller Flexner with experience in various litigation areas, including intellectual property.

Miller Fair Henry PLLC

• Garrett C. Parish

  • Role: Likely local counsel.
  • Firm Office Location: Tyler, Texas.
  • Relevant Experience: Garrett Parish is a partner at Miller Fair Henry PLLC, a firm based in Tyler, Texas, known for its intellectual property litigation practice in the Eastern District of Texas. His practice focuses on patent litigation, and he frequently serves as local counsel in the district.

• Andrea Leigh Fair

  • Role: Likely local counsel.
  • Firm Office Location: Tyler, Texas.
  • Relevant Experience: Andrea Leigh Fair is a partner at Miller Fair Henry PLLC, a Tyler, Texas-based firm. Her practice often involves intellectual property litigation in the Eastern District of Texas, where she likely serves as local counsel.

I'll research defense counsel through docket aggregators, firm websites, and press.

Strong leads. Let me verify the full counsel list, local counsel, and any in-house counsel.

Defense representatives — Microsoft Corp.

Bottom line: Microsoft is represented by Fish & Richardson P.C. as national trial counsel out of its Houston office, with The Dacus Firm, P.C. (Tyler, TX) acting as East Texas local counsel. This confirms and expands the Law360 data point flagged in the prior "Press & media coverage" section (which identified Fish & Richardson's Joseph R. Dorris but could not verify the firm's role): the Fish/Dacus defense team is now documented in Microsoft's own filed signature blocks. A separate Perkins Coie group represents Microsoft at the PTAB, not in this district court case.

Counsel of record for Microsoft Corporation

Fish & Richardson P.C. (national / lead trial counsel)

The Dacus Firm, P.C. (local counsel)

Important distinction: district court vs. PTAB counsel

Microsoft's Patent Trial and Appeal Board counsel is a different team from a different firm — Perkins Coie LLP — and should not be confused with district court counsel of record:

• Jessica C. Kaiser (Reg. No. 58,937) — Lead Counsel, Perkins Coie, Denver, CO.
• Back-up counsel: Christopher Marando (Washington, D.C.), Matthew A. Lembo (New York), Steven Beigelmacher (Seattle), Sarah Fowler (Palo Alto).
• In-house: Lucky Vidmar, Associate General Counsel, Microsoft, executed the power of attorney (dated 2025-12-12).

These names appear on Microsoft's POA and Sotera stipulations in the parallel IPRs against the same patents (IPR2026-00095, IPR2026-00174, and related filings). Perkins Coie appears only on the PTAB side in the documents I reviewed — I found no Perkins Coie notice of appearance in the district court docket. Flagging this because it is a plausible source of confusion when mapping "Microsoft's lawyers" across the two fora.

Docket-based confirmation and open questions

• The docket shows a wave of Microsoft-side appearance notices — D.I. 11–15 all filed 2025-09-05 (the same day as the first motion to dismiss, D.I. 16), plus D.I. 18–19 (Sept. 16–17, 2025), D.I. 23–25 (Sept. 29–30, 2025), and a pro hac vice appearance at D.I. 42 (Nov. 4, 2025). I was not able to map each individual appearance entry to a specific attorney name from the sources available, so the table above is grounded in filed signature blocks and the PACER Monitor appearance list rather than entry-by-entry matching.
• Post-February 2026 churn: the docket reflects a Withdraw as Attorney motion (D.I. 59, 2026-02-18) granted by order (D.I. 66, 2026-02-19), and later notices of appearance at D.I. 76 (2026-03-11) and D.I. 78 (2026-03-19). I could not determine which attorney withdrew or who newly appeared from the sources I retrieved. Anyone relying on this roster for service should check the current docket directly.
• Recency caveat: the consolidated docket listing I retrieved runs through roughly late March 2026, and the PACER Monitor "represented by" snapshot appears to date from about February 2026. Given today's date (2026-10-13), additional appearances, substitutions, or withdrawals may have occurred that are not captured here. Also note the second, later Microsoft suit flagged in the prior section (2:26-cv-00681, filed 2026-08-11), which may have its own counsel lineup.
• Microsoft is a named-party defendant; I found no in-house Microsoft attorney appearing of record in the district court case, as opposed to the PTAB in-house signatory noted above.

Sources

• Microsoft's Invalidity Contentions (served 2025-12-05), signature block listing Elacqua as Lead Counsel, Benedict, Dorris, Wang, Chang, Green and Dacus as "Counsel for Defendant Microsoft Corporation": PTACTS/USPTO copy and Docket Alarm copy
• PACER Monitor docket, 2:25-cv-00664 (appearance list)
• CourtListener docket, 2:25-cv-00664 (entry numbering / date sequence)
• Fish & Richardson biography — Benjamin C. Elacqua (Houston principal; Chamberlain $43M EDTX verdict; ITC and SEP practice)
• Law360 — Joseph R. Dorris and Claire Chang case listings
• The Dacus Firm — Deron Dacus (Tyler, TX; patent litigation and local-counsel practice)
• Microsoft POA and Sotera stipulation identifying Perkins Coie as PTAB counsel and Lucky Vidmar as in-house signatory: IPR2026-00174 POA and IPR2026-00095 Ex. 2002

Flag for the case file: as noted in the prior section, the case metadata lists only the '903 patent and the case-overview section calls it the "sole patent asserted," but Microsoft's own briefing and the operative second amended complaint confirm six asserted patents ('903, '466, '053, '883, '692, '173). The defense team described above is defending all six in this action.