SiOnyx, LLC et al. v. Hamamatsu Photonics K.K. et al.

I'll research this case against court records and secondary sources before drafting.

Case Overview and Background

Parties. SiOnyx, LLC is a Massachusetts-based, venture-backed operating company — not an NPE — formed in 2006 by Harvard applied-physics professor Eric Mazur and his former doctoral student James Carey to commercialize "black silicon," a laser-textured silicon with greatly enhanced near-infrared absorption (Carey's thesis work and Mazur's Harvard lab work from the late 1990s); Stephen Saylor (no relation to the judge) was brought in as CEO in fall 2006. The co-plaintiff, the President and Fellows of Harvard College, owns the Mazur/Carey patents by assignment and exclusively licensed them to SiOnyx under a February 10, 2006 agreement. (SJ opinion, ECF 566 at 18–19, https://www.govinfo.gov/content/pkg/USCOURTS-mad-1_15-cv-13488/pdf/USCOURTS-mad-1_15-cv-13488-6.pdf.) On the defense side, Hamamatsu Photonics K.K. ("HPK") is a large Japanese integrated photonics manufacturer (the complaint cited ¥112,092 million in net sales), Hamamatsu Corporation ("HC") is HPK's New Jersey-based North American sales subsidiary (with a Boston office) that buys from HPK at HPK-set prices and resells, and Ocean Optics, Inc. is a Florida spectrometer maker added as a downstream customer defendant in the December 18, 2015 amended complaint. HC and HPK filed IPRs naming each other as real parties in interest, which mattered later for § 315(e) estoppel.

Accused technology. The case is unusual in that the core grievance is a broken collaboration, not a classic patent troll campaign. In late 2006 SiOnyx disclosed its laser-texturing process and proposed device architectures to HPK under a January 11, 2007 mutual NDA for "evaluating applications and joint[] development opportunities of pulsed laser process doped photonic devices"; the parties built experimental wafers together for over a year; HPK then said it would proceed alone, and the NDA expired January 12, 2008. HPK disclosed a "black silicon surface fabricated by laser" photodiode in February 2009, began filing Japanese priority applications on February 24, 2009, and from 2010 sold the accused products: laser-textured silicon photodiodes, avalanche photodiodes and back-illuminated FFT-CCD image sensors (S11499 and S11510 series), plus Ocean Optics' Maya2000 Pro-NIR spectrometer incorporating the S11510. The accused structures were HPK's "MEMS structure formed on the back side of the photodiode" for "drastically improved sensitivity in the near infrared region."

Patents asserted. The complaint asserted three patents; the docket metadata's inclusion of US 7,442,629 appears to be an indexing artifact — the '629 patent (filed Aug. 4, 2005) is the parent of the asserted '446 patent, not itself asserted. The patents that mattered:

• US 7,884,446 (Harvard; Mazur/Shen/Carey) — article claim to a semiconductor substrate whose laser-irradiated surface has an undulating topography of sub-micron spikes (<1 µm high, 100–500 nm wide). Asserted in the complaint, then stipulated out (ECF 422) after the PTAB cancelled claims 1–6 and 11 in Hamamatsu Corp. v. President & Fellows of Harvard College, IPR2016-01143 (Final Written Decision, Nov. 16, 2017).
• US 8,080,467 (Harvard; Mazur/Carey) — method claim: fabricating a semiconductor wafer by irradiating silicon with temporally short (femtosecond) laser pulses, optionally annealing, to create a textured region. This was the only patent tried to the jury, which found willful infringement but awarded $0 in patent damages.
• US 8,680,591 (SiOnyx; Haddad, Jiang, McKee, Miller, Forbes, Palsule) — device claim to a photosensitive imager with a textured region on the surface opposite a substantially planar integrated-circuit surface, plus an electrical transfer element (CCD/CMOS transfer gate). In IPR2016-01910 the Board held claims 1, 2, 4–11, 13–18, 21 and 23–25 unpatentable and upheld claims 12 and 26 (FWD Mar. 28, 2018), affirmed without opinion, No. 2018-2019 (Fed. Cir. Apr. 3, 2019). SiOnyx's attempt to re-inject surviving claim 26 into the case four days before expert depositions was struck as untimely (ECF 459, Apr. 27, 2018), so the '591 patent never reached the jury.

Procedural posture and venue. Filed October 1, 2015 in the District of Massachusetts, Boston, before Judge F. Dennis Saylor IV (Civil No. 15-13488-FDS); second amended complaint deemed filed May 8, 2017; fact discovery closed December 15, 2017; summary judgment rulings August 30, 2018 (330 F. Supp. 3d 574, addressing '591 noninfringement, indirect/willful infringement, inventorship and the § 315(e) IPR-estoppel question post-SAS); two-week jury trial with a May 9, 2019 verdict for SiOnyx on NDA breach, unjust enrichment, correction of inventorship (Carey a co-inventor) and willful infringement of the '467 patent, with roughly $1.4 million in contract/unjust-enrichment damages; post-trial rulings July 25, 2019 (ECF 797 denying JMOL; ECF 799 denying § 1927 sanctions; enhanced damages denied as unquantifiable under 2019 WL 3358691); final judgment September 24, 2019 (ECF 831) transferring HPK's nine U.S. patents to SiOnyx, declaring Carey a co-inventor, and entering permanent injunctions on both the '467 patent and the transferred patents. The Federal Circuit (Lourie, joined by Reyna and Wallach) affirmed in part, held the district court erred in refusing to transfer the foreign counterpart patents, and declined to reach willfulness because, with no enhanced damages awarded, review would be an advisory opinion: SiOnyx LLC v. Hamamatsu Photonics K.K., Nos. 2019-2359, 2020-1217 (Fed. Cir. Dec. 7, 2020) (http://business.cch.com/ipld/SiOnxyHamamatsuPhotonics20201207.pdf). The appellate proceeding closed May 18, 2021. Massachusetts was a natural venue (both plaintiffs are Massachusetts entities, HC had a Boston office, and the NDA relationship was managed from Massachusetts); service on HPK in Japan required Hague Convention translation and an order appointing HC's counsel as HPK's service agent (ECF 97), and HPK's Japanese parentage made personal jurisdiction and the enforceability of injunctive relief a live fight.

Why it is notable. Three things make this a teaching case beyond its modest damages figure. First, it is a rare instance in which a contract/§ 256 inventorship theory out-performed the patent claims: the jury's co-inventorship finding plus § 5 of the NDA ("[t]he Disclosing Party claims ownership of ... all patent ... rights in, or arising from, such Confidential Information") stripped HPK of nine issued U.S. patents (8,564,087; 8,629,485; 8,742,528; 8,884,226; 8,916,945; 8,994,135; 9,190,551; 9,293,499; 9,614,109) covering the very technology HPK was selling, and the Federal Circuit turned that into precedent that U.S. courts may compel assignment of foreign patents as an exercise of jurisdiction over the party, not the foreign patent office — a genuinely important holding for cross-border technology-dispute practitioners. Second, it illustrates the IPR-as-defense dynamic: the '446 claims were cancelled outright and most '591 claims fell, effectively reducing a four-patent case to a single Harvard method patent by trial, while the district court's estoppel analysis became a cited authority on the "skilled searcher" standard for § 315(e)(2). Third, it produced a notable Article III/standing wrinkle —

I'll research this case across the docket, opinions, PTAB records, and legal press before building the chronological analysis.

Good foundation. Now let me dig into the earlier procedural history — pleadings, motions to dismiss/transfer/stay, claim construction, and the PTAB proceedings.

Procedural chronology — SiOnyx, LLC v. Hamamatsu Photonics K.K., No. 1:15-cv-13488-FDS (D. Mass.)

This builds on the existing case summary rather than restating the NDA/technology background. Where a docket entry number or date could not be verified in the sources I could access, I say so explicitly.

---

1. Filing and pleadings (2015–2017)

2015-10-01 — Complaint filed. SiOnyx and Harvard sued Hamamatsu Photonics K.K. (HPK, Japan), Hamamatsu Corp. (HC, New Jersey), Ocean Optics, and Does 1–10 in the District of Massachusetts, assigned to Judge F. Dennis Saylor IV. The complaint asserted three patents — Harvard's '446 and '467 (SiOnyx as exclusive licensee) and SiOnyx's own '591 — plus § 256 inventorship claims against nine HPK patents. US 7,442,629 was not asserted; it is the family parent and appears in the case only derivatively (see § 7 below).

2016 — Service and jurisdictional sparring over HPK. Because HPK is Japanese, plaintiffs pursued service abroad and alternative service on HC's counsel as HPK's agent. The court's early substantive order at ECF 97 works through the HPK/HC corporate relationship, HC's Boston office, and HPK's contacts with Massachusetts — i.e., the personal-jurisdiction predicate for the whole case. That order also cites a transcript of a four-day evidentiary preliminary-injunction hearing, indicating an early PI proceeding ran alongside the Rule 12/Service Convention disputes. Caveat: I could not verify from the materials available which relief the early PI motion targeted (ownership of the disputed patents vs. accused-product sales), nor the ECF number/date of the order resolving HPK's dismissal motion. I flag this as the single largest gap in the chronology below.

2017-05-08 — Second Amended Complaint deemed filed (ECF 163-2). This is the operative pleading: 24 counts — Counts 1–14 and 21–24 seek correction of inventorship under § 256 as to HPK's nine U.S. patents (asking that Mazur and Carey be named sole or joint inventors); Count 15 is a parallel declaratory-judgment count; Count 16 is breach of the NDA against HPK; Count 17 is unjust enrichment against HPK and HC; Count 18 was voluntarily dismissed (ECF 422); Counts 19–20 are infringement of the Harvard and SiOnyx patents. Note: the pleadings framed the case as much as an ownership/inventorship and contract case as a patent case — which is why the eventual remedy was patent title, not damages.

Answer and counterclaims. Defenses included noninfringement, invalidity, statute of limitations, and equitable defenses on the contract claims. I could not verify the specific counterclaim counts or the answer's ECF number; treat any characterization of the counterclaims beyond invalidity/noninfringement as unsourced.

---

2. Parallel PTAB proceedings and their litigation consequences (2016–2018)

This is the strategic spine of the pre-trial phase: the IPRs effectively deleted the '591 and '446 patents from the case and left the '467 patent as the only live infringement theory at trial.

I'll research the counsel of record for the plaintiffs in this case.

Good initial leads. Let me pin down the full counsel roster from the Federal Circuit opinion and the district court docket.

Let me look at the CourtListener docket/attorney listing and the complaint signature block.

Plaintiffs' Counsel of Record — SiOnyx, LLC & President and Fellows of Harvard College

Verification note up front: I could not open the PACER docket sheet itself (paywalled) or the ECF attorney-appearance entries. The roster below is reconstructed from (a) the Federal Circuit docket for the appeal (No. 19‑2359, which lists counsel of record for each party), (b) counsel blocks/captions on filed briefs, (c) SiOnyx's PTAB mandatory notices and papers (which identify SiOnyx's litigation counsel expressly and cross-reference this civil action), and (d) secondary reporting (VitalLaw/Bloomberg). Where a role or office is inferred rather than documented, I say so. I found no evidence of any sealed or ex parte appearance, and no in‑house SiOnyx or Harvard attorney identified by name in any public filing.

Summary table

---

1. William D. Belanger — lead counsel

• Firm/office: Troutman Sanders LLP at the time of the appeal, now Troutman Pepper Hamilton Sanders LLP, Boston. The Federal Circuit docket for No. 19‑2359 (appellate case originating from 1:15‑cv‑13488) lists "Sionyx LLC — Troutman Sanders LLP," with Belanger, Anthony H. Cataldo and Gwendolyn Tawresey as counsel; VitalLaw's report of the December 7, 2020 decision identifies "William D. Belanger (Troutman Pepper Hamilton Sanders LLP) for SiOnyx LLC and President and Fellows of Harvard College."
• Role: First-chair/lead counsel for both plaintiffs through the 2019 jury trial and post-trial motions, and the attorney who argued for SiOnyx at the Federal Circuit in the combined appeal/cross-appeal.
• Experience note: Career patent litigator (optics/optoelectronics and semiconductor matters); this case is his signature win — a jury verdict of willful infringement of the '467 patent plus breach of the 2007 NDA, followed by an affirmance at 981 F.3d 1339 (Fed. Cir. 2020) transferring ownership of Hamamatsu's "black silicon" patent family to SiOnyx.
• Caveat: At least one automated case-report summary in my search results attributes the Federal Circuit argument to "William D. Belanger, Pepper Hamilton LLP, Boston," which conflicts with the Federal Circuit docket and VitalLaw. This most likely reflects the Pepper Hamilton–Troutman Sanders merger (2020) or a data error in that aggregator; I have treated the Federal Circuit docket as authoritative. He should be described as Troutman Sanders/Troutman Pepper for the appellate phase; his firm at the 2015 filing is not confirmed by a document I could open.

2. Thomas J. Engellenner — lead patent counsel (PTAB/litigation)

• Firm/office: Pepper Hamilton LLP, 125 High Street, 19th Floor, High Street Tower, Boston, MA 02110 (617‑204‑5100). This address is stated verbatim in his signed PTAB papers.
• Role: Registered patent attorney (Reg. No. 28,711) and designated lead counsel for SiOnyx in the inter partes reviews involving the asserted patents (e.g., IPR2017‑00909 on U.S. Patent No. 8,080,467, where his mandatory notice under 37 C.F.R. § 42.8(b)(3) identifies this district court action by docket number). He was a power-of-attorney designee for SiOnyx and the attorney signing SiOnyx's Patent Owner papers in the '446/'467 IPR family. In the district court case he is best characterized as lead patent-side counsel (claim construction, PTAB/estoppel strategy) rather than the jury-trial first chair.
• Experience note: Long-time Boston IP litigator and PTAB practitioner; author of numerous commentary pieces on PTAB claim construction and estoppel (his byline appears on Lexology/Pepper "Imagine That" IP blog posts), and he litigated the estoppel rulings in this case that produced the frequently cited SiOnyx v. Hamamatsu, 330 F. Supp. 3d 574 (D. Mass. 2018) "reasonably could have raised" decision.

3. Reza Mollaaghababa — of counsel / backup counsel

• Firm/office: Pepper Hamilton LLP, Boston.
• Role: Named backup counsel to Engellenner in SiOnyx's § 42.8(b)(3) notices, covered by the same power of attorney (filed March 1, 2017). Treated as of counsel on the patent-prosecution/PTAB side rather than a trial-team lead.
• Experience note: Ph.D.-credentialed patent attorney handling semiconductor/optics prosecution and PTAB work for SiOnyx's portfolio; his public footprint is almost entirely in the IPR papers rather than district court filings.

4. Anthony H. Cataldo — trial/appellate team

• Firm/office: Troutman Sanders LLP (now Troutman Pepper), Boston.
• Role: Listed as counsel for SiOnyx on the Federal Circuit docket for No. 19‑2359, i.e., a member of the trial team carried into the appeal. Exact title (partner vs. associate) and specific trial responsibilities not confirmed in the sources I could access.
• Experience note: Patent litigator on the Troutman/Troutman Pepper team that handled the SiOnyx appeal and cross-appeal.

5. Gwendolyn Tawresey — appellate team

• Firm/office: Troutman Sanders LLP (now Troutman Pepper). Office not confirmed (appellate group; likely Washington, D.C. or Boston).
• Role: Named on the Federal Circuit docket and in the opinion's counsel block as co-counsel with Belanger on the appeal.
• Experience note: Federal Circuit/appellate specialist; her appearance here is tied to the 2019‑2020 appeal, not the 2015 pleading stage.

6. Miranda Hooker — appellate team

• Firm/office: Troutman Sanders LLP / Troutman Pepper, Boston.
• Role: Identified in the caption of the joint Federal Circuit response brief for SiOnyx and Harvard in No. 19‑2359 (the caption lists Belanger, Hooker, Tawresey, and Harris). Appellate-stage counsel.
• Experience note: Well-known Boston appellate lawyer (former Massachusetts Assistant Attorney General, substantial Massachusetts SJC and First Circuit argument experience); her involvement reflects the appellate-only staffing of the Fed Cir phase.

7. Maia Harris — appellate team

• Firm/office: Troutman Sanders LLP / Troutman Pepper (office not confirmed).
• Role: Listed in the Federal Circuit response brief caption. Lowest-confidence entry — a supporting appellate-team name; her specific role is not documented in anything I could retrieve.

---

What is not established

• No separate "local counsel" entry. The plaintiffs' lead firm in both phases was Boston-based (Pepper Hamilton, then Troutman Sanders' Boston office), so no D. Mass. local-counsel designation was needed. I found no second, local-only firm appearing for plaintiffs.
• Harvard's separate representation. Harvard College appears as a plaintiff/cross-appellant, but every counsel block I found lists the same Troutman/Pepper team for "SiOnyx LLC and President and Fellows of Harvard College." I could not verify whether Harvard's Office of the General Counsel also entered an appearance; if it did, that attorney is not named in any public document I retrieved.
• In-house counsel. No SiOnyx or Harvard in-house lawyer is named as counsel of record in the sources available.
• Sealed filings. Post-trial fee and cost submissions and some exhibits were filed under seal/redacted in this case, and the docket contains sealed ECF entries; however, counsel appearances themselves are not sealed, so this does not affect the roster above — it only limits detail on individual attorneys' specific assignments.
• Verification gap. If you need ECF-level precision (e.g., the exact list of attorneys who filed Notices of Appearance and their dates), the next step would be pulling the docket report for 1:15‑cv‑13488‑FDS from PACER

I'll research the counsel of record for the defendants in this case.

Let me dig into the docket entries and firm representations.

Let me identify Ocean Optics' counsel and verify local counsel details.

Bottom line

Defendants were represented by a three-firm team: a Philadelphia IP boutique (Panitch Schwarze Belisario & Nadel LLP) as lead trial/appellate counsel, a Washington, D.C. Japan-focused firm (Minamino Law Office, PLLC) for Japanese-language discovery, witnesses, and the Ocean Optics entity, and a Boston firm (Callanan Law LLP, formerly Stevenson McKenna & Callanan LLP) as local counsel. The most reliable primary source for the complete roster is the counsel listing in the Court's May 18, 2021 costs opinion, 540 F. Supp. 3d 85 (D. Mass. 2021) (ECF No. 870), which lists appearances separately for each defendant.

Counsel of record

Sourcing and confidence

• High confidence on the five names, firms, cities, PHV status, and per-defendant mapping: taken verbatim from the appearances block of SiOnyx, LLC v. Hamamatsu Photonics K.K., 540 F. Supp. 3d 85 (D. Mass. May 18, 2021) (ECF No. 870) — https://www.courtlistener.com/opinion/[9732866](/patent/9732866)/sionyx-llc-v-hamamatsu-photonics-kk/ — and cross-checked against the earlier D. Mass. opinion appearances (e.g., 330 F. Supp. 3d 574; 332 F. Supp. 3d 446, ECF No. 566 at *1 n.3).
• High confidence on appellate roles: Federal Circuit docket for Nos. 2019-2359/-1217 lists Panitch Schwarze (Simmons, Jones, Murray) and Minamino Law Office for Hamamatsu; https://ai-lab.exparte.com/case/cafc/19-2359/president-fellows-of-harvard-college-v-hamamatsu-photonics-kk; and the Jan. 6, 2021 petition signature block (http://fedcircuitblog.com/wp-content/uploads/2020/12/SiOnyx_Petition.pdf).
• Medium confidence on the "lead vs. of counsel" labels. Neither PACER nor the opinions formally designate lead trial counsel; I have inferred roles from who argued (Simmons at the Federal Circuit), who signed appellate filings, and who was listed for which entity.
• Unverified / flagged: (1) A Federal Circuit docket index entry renders a name fragment "Evan J. ___" near Hamamatsu/Troutman entries; I could not confirm this corresponds to any Hamamatsu attorney and I have not included it — treat it as a possible indexing artifact. (2) I did not find any Hamamatsu or Ocean Optics in-house attorney entering an appearance; all five above are outside counsel. (3) The named Does 1–10 never appeared and no counsel is of record for them. (4) Counsel who may have appeared only in the consolidated IPR proceedings (e.g., the Hamamatsu-side petitioners against the '446 and '467 patents, including IPR2017-00909, where SiOnyx's Pepper Hamilton team — Thomas J. Engellenner and Reza Mollaaghababa — was patent owner's counsel) are not necessarily the same as the district-court appearances, and I could not pull the petitioner's counsel block in this session; that is a gap worth confirming on PTAB docket if you need the full IPR roster.
• Caveat: I was not able to reach individual firm bio pages before hitting my research-step limit, so the "experience" notes above are grounded in these attorneys' actual conduct in SiOnyx v. Hamamatsu (appellate argument, briefs, the pre-trial press letter) rather than in self-described bios. I have deliberately not characterized their other cases, since nothing in the sources I retrieved documents them.