Karl R. Leinsing

Karl R. Leinsing — Patent Litigation Practice Summary

Specialty / focus. Leinsing is a mechanical engineer (MSME, PE) and medical-device product designer who works in patent litigation as a technical expert on infringement, validity, and prior art — not as counsel of record. His engagements cluster in medical devices and related mechanical/fluidic systems: IV disposables and needle-free valves, infusion and pen injectors, cardiovascular and tissue-anchor implants, hydrodermabrasion/skin-treatment systems, glucose sensors, and e-cigarette/vaping hardware. His CV lists patent and liability testimony in the U.S., Canada, EPO, USPTO, ITC, and Australia.

Side preference. He works both sides. In the tracked HydraFacial matters (Eunsung Global Corp. v. HydraFacial LLC), he appears for the patent owner, submitting expert declarations in IPRs IPR2024-01491, IPR2025-00445, IPR2025-00145, and IPR2025-01169 and testifying in parallel ITC investigations (e.g., Inv. No. 337-TA-1408). Elsewhere he has testified for defendants (R.J. Reynolds in Altria v. RJR Vapor; Abbott in the Dexcom wars; Sandoz in Novo Nordisk v. Sandoz) and for plaintiffs (e.g., Canning v. Medtronic). Note: the "Attorney for Patent Owner" label in the tracking data reflects his role as HydraFacial's expert declarant — he is not admitted to practice law.

Firm context. He is founder and president of ATech Designs, Inc. (Dover, NH), a medical-device development and litigation-consulting firm he has led since 2006; the practice traces to Innovative Engineering, Inc. (North Carolina, 1998). Earlier he was a senior principal design engineer at IVAC/IMED/Eli Lilly/ALARIS/Cardinal Health/CareFusion/BD (1992–2002), manager of design engineering at ONUX Medical, and director of biomedical engineering at Mitralign. He holds 40+ U.S. patents, including the SmartSite needle-free valve sold by BD.

Notable cases / outcomes. Prominent matters include Minerva Surgical v. Hologic (D. Del.), where the court denied a motion to exclude his infringement/validity testimony (2021); Altria v. R.J. Reynolds Vapor (M.D.N.C.), where he served as Reynolds' invalidity expert on the Hawes vaping patents; Abbott Diabetes Care v. Dexcom (D. Del./W.D. Tex.); and the HydraFacial hydrodermabrasion IPRs and ITC investigations, which settled or were terminated in 2025–2026. He also testified in Auge v. Stryker, where portions of his opinions were excluded as invading the jury's role.

PTAB/IPR experience. Extensive — he is a frequent IPR/PGR declarant, with declarations in IPR2015-00693 (Ivera Medical), IPR2019-00208/223, IPR2021-00746, IPR2022-00917, IPR2022-01347, and multiple HydraFacial IPRs, plus depositions and cross-examination in those proceedings.

Bar / education. Not a bar member. B.S. Mechanical Engineering, University of New Hampshire (1988); M.S. Mechanical Engineering, North Carolina A&T State University (1995); licensed Professional Engineer, New Hampshire (1992).