Patent Landscape and Intellectual Property

The CGM patents that matter most belong to the companies that make the sensors, and many of the earliest ones have already run out. A US patent normally ends 20 years after its application was filed [1], so continuous glucose monitor (CGM) patents filed in the late 1990s have expired, as the records below show. The patent fight between Abbott and Dexcom ended in a settlement announced in December 2024 [2].

How long a CGM patent lasts

The basic rule sits in 35 U.S.C. 154. A US patent's term starts when it issues and ends 20 years from the US filing date, or from an earlier application it formally relies on, and the owner has to keep paying maintenance fees to keep it alive [1]. Two mechanisms can push that end date later.

Patent term adjustment adds days when the patent office misses its own deadlines, for example by taking more than three years to issue a patent; it applies to applications filed on or after May 29, 2000 [3]. Patent term extension is different. Created by the Hatch-Waxman Act of 1984, it gives back some of the patent life a product lost while waiting for government premarket approval, and medical devices qualify [4].

Here's what surprised us: term extensions are one of the few places where a public patent record names a product. The law extends "a patent which claims a product" that went through premarket review [4]. Abbott's US5262035, "Enzyme electrodes," was filed in 1989 by Brian Gregg and Adam Heller, originally assigned to a company Google Patents lists as Heller E and Co, and now sits under Abbott Diabetes Care [5]. Its first claim covers an electrode coated with a crosslinked polymer that holds an enzyme and carries its signal to the electrode [5]. An extension request filed in 2008 named the FreeStyle Navigator Continuous Glucose Monitoring System, and the grant in 2012 moved the patent's expiry from November 16, 2010 to November 15, 2015 [5].

The Navigator itself is long gone. FDA approved it for Abbott Laboratories on March 12, 2008, and FDA's approval database records a withdrawal date of March 18, 2013 [6].

The first wave of CGM patents has expired

Three more records show what the first generation looks like as of October 2026. Google Patents gives all three the status "Expired - Lifetime" [7][8][9].

• Dexcom, US6001067, "Device and method for determining analyte levels." Mark Shults, Stuart Updike and Rathbun Rhodes filed it on March 4, 1997. The record lists the original assignee as "Individual" and the current one as Dexcom [7]. Its first claim describes a device for measuring glucose with a housing, electrodes and a membrane impregnated with an oxidase enzyme [7].
• Abbott, US6134461, titled "Electrochemical analyte" in the record. It was filed on March 4, 1998, assigned to the same Heller company, and now sits under Abbott Diabetes Care. Its abstract describes an implantable sensor built from conductive traces on a substrate for continuous monitoring of analytes such as glucose [8].
• Senseonics, US6330464B1, "Optical-based sensing devices." It was filed on August 26, 1999 and assigned to Sensors for Medicine and Science, which the assignment record later shows changing its name to Senseonics [9]. It claims a light-guiding sensor body with a built-in light source and an indicator whose optical properties change with analyte concentration; the abstract gives fluorescence as one example [9]. Our article on implantable fluorescence sensors covers the physics behind that idea.

A granted patent can still change. Both of the electrochemical patents went through reexamination, a second review by the patent office after the patent issued. The Abbott record lists reexamination requests filed in 2006, 2007 and twice in 2010; a 2010 certificate amended claim 1 and added claims 30 through 188, and a 2014 certificate cancelled claim 143 and amended five others [8]. The Dexcom patent went the other way. After a 2011 request, the patent office cancelled all of its claims in 2014 [7].

A newer patent, read carefully

Companies kept filing on later work, so the early expiries aren't the whole story. MiniMed's US9649059B2, "Methods and systems for improving the reliability of orthogonally redundant sensors," is assigned to Medtronic MiniMed, Inc. It was filed on April 24, 2014 and granted on May 16, 2017 [10].

"Orthogonally redundant" means two sensors that measure glucose in different ways. Here that's an optical sensor and an electrochemical sensor in one device, with software that checks each signal for sensitivity loss, noise and drift before calibrating and combining the readings [10]. As of October 2026 the record shows it as active, with maintenance fees paid in 2020 and 2024, and Google Patents gives an "adjusted expiration" of November 27, 2034 [10]. That's about seven months past the plain 20-year date, the kind of gap patent term adjustment produces [3].

What the record leaves out matters as much. A patent shows what a company claimed, not what it ships. Nothing in this record says a MiniMed sensor uses dual optical and electrochemical sensing, and we'd need labeling or a company statement before saying one does.

Interoperability changed what companies share

FDA's integrated CGM (iCGM) device class is built around sharing data with other devices. Under 21 CFR 862.1355, an iCGM is "designed to reliably and securely transmit glucose measurement data to digitally connected devices, including automated insulin dosing systems" [11]. Its special controls also require a detailed strategy for getting readings to receiving devices securely, reliably and at clinically meaningful intervals [11].

The effect shows up in compatibility lists. As of October 2026, Insulet says its Omnipod 5 pump integrates with Dexcom G7 for ages 2 and up, Dexcom G7 15 Day for ages 18 and up, and the FreeStyle Libre 3 Plus and Libre 2 Plus sensors [12]. MiniMed went further. In December 2025 it began the US launch of the MiniMed 780G system with the Instinct sensor, which its release describes as "made by Abbott and designed exclusively for MiniMed systems" [13].

That release describes a product partnership. It doesn't disclose patent or licensing terms [13], so we can't say how the two companies divide the intellectual property behind the Instinct sensor. For how these sensor-to-pump connections work, see our page on interoperability with automated insulin delivery.

How the Abbott and Dexcom dispute ended

On December 23, 2024, Abbott announced it had settled all outstanding patent disputes with Dexcom in cases related to CGM products [2]. Every pending case in courts and patent offices worldwide was to be dismissed. Neither company paid the other, and both agreed not to litigate patent, trade dress or design rights disputes with each other for the next 10 years [2].

The details are confidential, and Abbott's announcement doesn't mention a cross-license [2]. Counted from the announcement, the 10-year standstill runs to December 2034.

Reading a patent record yourself

Google Patents pages are free to read. The assignee fields show who owned a patent when it issued and who holds it now, which is how a 1989 Heller filing appears under Abbott Diabetes Care [5], and the legal-events table lists reexaminations, maintenance fees and term extensions [5][7]. The expiry date on those pages is Google's "anticipated" or "adjusted" figure [7][10], so anything with legal stakes belongs with the USPTO's own file.

The biggest question stays open. Of the five records we read, only the Navigator extension tied a patent to a named product [5], and none of them connects a patent to a CGM sold as of October 2026.