United States Patent 6,718,972: Claim Scope, Patent Strength, Expiration and Inhaler Patent Landscape

U.S. Patent No. 6,718,972 protects a breath-actuated dry-powder inhaler architecture that combines a hinged mouthpiece cover, a reservoir-fed metering cup, a three-position yoke, paired cam tracks, dose resetting, and optional dose counting, de-agglomeration, pressure relief, and reservoir pressurization. Independent claim 1 is the principal broad claim. Claims 2 through 20 narrow the device through specific mechanical and airflow configurations.

The patent is a device patent, not an active-ingredient patent. Its claims do not protect a particular drug, formulation, dosage strength, or therapeutic indication. The principal infringement risk historically applied to inhalers using the claimed mechanical sequence for metering and resetting a dose from a bulk dry-powder reservoir.

What does U.S. Patent 6,718,972 protect?

The patent protects a medicament inhaler with the following mandatory combination:

A mouthpiece and hinged cover.
A delivery passageway leading to the mouthpiece.
A channel connected to the delivery passageway.
A medicament reservoir with a dispensing port.
A metering cup movable between the reservoir port and delivery passageway.
A spring biasing the cup.
A yoke with a ratchet that controls cup movement.
Two cams attached to the hinged cover.
Three successive cam surfaces on each cam.
Cam followers on the yoke.
A spring forcing the followers against the cam surfaces.
A defined sequence in which opening and closing the cover moves the yoke through three positions.

A product that lacks any required element of claim 1 does not literally infringe claim 1. The claim is therefore broad at the system level but narrow in its required mechanical combination.

What is the central inventive concept?

The central concept is synchronized dose metering through cover movement. Opening the cover does more than expose the mouthpiece. It mechanically drives the yoke through successive positions, causing the metering cup to move between the reservoir and the airflow path. Closing the cover reverses the sequence and returns the mechanism to its initial condition.

The claim links four functions:

Function	Claimed mechanism
Dose storage	Reservoir containing medicament
Dose measurement	Cup sized or positioned to receive a dose
Dose transfer	Cup movement between reservoir port and delivery passageway
Mechanical sequencing	Hinged cover, cams, cam followers, yoke and ratchet

The claim does not require electronic actuation, a particular inhalation threshold, a specific dry-powder formulation, or a particular pharmaceutical compound.

How broad is independent claim 1?

Claim 1 is an apparatus claim with a dense set of structural and functional limitations. Its practical scope depends on whether a competing inhaler uses the same three-stage cam and yoke sequence.

Claim 1 limitation map

Claim element	Scope implication
Hinged cover	Requires a cover movable about a hinge
Delivery passageway	Requires a defined airflow route to the mouthpiece
Reservoir and dispensing port	Requires bulk or compartmentalized medicament storage with an outlet
Cup	Requires a movable metering member characterized as a cup
Cup spring	Requires spring bias toward the dispensing port or delivery passageway
Yoke	Requires a yoke engaging the cup
Ratchet	Requires a ratchet that selectively blocks or permits cup movement
Two cams	Requires two cam structures secured to the cover
Three cam surfaces	Requires first, second and third surfaces successively spaced from the hinge
Cam followers	Requires follower elements on the yoke
Three positions	Requires sequential yoke movement through three positions
Opening sequence	Requires engagement of the three cam surfaces during opening
Closing sequence	Requires return through the positions during closing

The most important limitations are the two cams, three cam surfaces, three yoke positions, and ratchet-controlled cup movement. A competing inhaler using a rotary valve, sliding blister, fixed dose cavity, or electronic indexing system may avoid literal infringement even if it performs the same general dosing function.

Does the claim require a dry-powder inhaler?

Claim 1 itself does not expressly require dry powder. Claim 6 adds a reservoir containing dry powdered medicament, and claim 18 specifies that the cup holds a predetermined dose of dry powder. Claims 7, 8, 10 and 19 also contain features particularly suited to dry-powder delivery.

A device using a liquid or aerosolized medicament could potentially fall within claim 1 if all structural limitations were present, although the claim's reservoir, cup and inhalation architecture is directed commercially toward dry-powder systems.

What do claims 2 through 20 add?

The dependent claims create narrower positions around dosing, airflow, counting, sealing and manufacturing details.

Metering and reset claims

Claims 2 through 4 and 16 through 18 focus on the cup and yoke.

Claim 2 requires the cup spring to bias the cup toward the delivery passageway.
Claim 3 adds a yoke push bar that returns the cup to the reservoir port.
Claim 4 requires the ratchet to block cup movement in two yoke positions and permit movement in the third.
Claim 16 requires a resiliently movable ratchet.
Claim 17 specifies a flexible flap carrying the ratchet.
Claim 18 requires the cup to hold a predetermined dry-powder dose.

These claims are narrower than claim 1 but may be more technically useful in infringement analysis because they identify the reset mechanism with greater precision.

De-agglomerator and airflow claims

Claims 7 and 8 cover an airflow de-agglomerator between the delivery passageway and mouthpiece. Claim 8 requires:

A swirl chamber;
A supply port and outlet port;
At least two diametrically opposed inlet ports;
Tangential inlet orientation;
Radial vanes at the top of the chamber;
Collision between at least part of the entering air streams and the vanes.

This limitation set is materially narrower than a general turbulence chamber. An inhaler with a different de-agglomeration geometry, such as a grid, impaction screen, spiral channel or single tangential inlet, may avoid claim 8.

Dose-counter claim

Claim 9 adds a mechanical dose counter with:

A bobbin;
A rotatable spool;
A rolled ribbon with indicia;
Spool teeth;
A yoke pawl that advances the ribbon.

The claim is directed to a ribbon-based mechanical counter integrated with yoke movement. A digital counter, printed rotating disk, or independent actuator may fall outside this claim.

Pressure-relief and sealing claim

Claim 10 is one of the most technically specific claims. It requires:

A pressure-relief port in the channel;
A conduit between the reservoir interior and the relief port;
A cup recess for receiving medicament;
A first sealing surface for the reservoir dispensing port;
A second sealing surface for the pressure-relief port;
Opposite sealing behavior depending on cup alignment.

This claim addresses pressure management and powder containment during cup movement. It may be relevant to devices that use reservoir pressurization or pneumatic assistance.

Cam and cover construction claims

Claims 5 and 11 through 15 concern the cam structures.

Claim 5 requires cam rotation about the hinges.
Claim 11 requires openings through which the hinges pass.
Claim 12 adds bosses received in cover recesses.
Claim 13 defines closed, partially open and fully open cam positions.
Claim 14 fixes the relative spacing of the first, second and third cam surfaces.
Claim 15 requires discrete cams assembled to the cover.

Claims 11, 12 and 15 are useful in manufacturing and teardown analysis because they concern physical construction rather than only operating sequence.

Bellows claim

Claims 19 and 20 add a resiliently collapsible bellows connected to the reservoir. The yoke collapses the bellows during engagement with the second and third cam surfaces and permits expansion when the yoke returns to the first position.

This is a distinct subcombination involving reservoir pressurization. A device can infringe claim 1 without infringing claims 19 or 20.

What is the patent's likely expiration and current enforceability?

U.S. Patent 6,718,972 issued on April 13, 2004. Its enforceable term is governed principally by 35 U.S.C. §154, which generally provides 20 years from the earliest effective U.S. nonprovisional filing date, subject to patent-term adjustment, terminal disclaimers and other statutory modifications (35 U.S.C. §154).

For a patent filed around 2000, the ordinary term would generally have ended around 2020, subject to any patent-term adjustment. Accordingly, the patent is not expected to provide a current blocking right in 2026. The precise expiration date requires the USPTO patent record, including the term-adjustment calculation and any terminal disclaimer.

The patent's commercial significance is therefore historical unless a later continuation, divisional, reissue or related family member carries overlapping claims into a later term.

What is the Orange Book status of U.S. Patent 6,718,972?

U.S. Patent 6,718,972 is a mechanical inhaler patent rather than an active-ingredient or drug-label patent. It would not ordinarily be listed in the FDA Orange Book merely because it covers an inhaler mechanism.

Orange Book patent listings generally relate to patents claiming the approved drug substance, drug product, formulation or method of use. A device patent may become relevant to an abbreviated new drug application only in limited circumstances, particularly where the device is part of the approved drug product and the listed patent meets applicable statutory and regulatory criteria. The patent number should therefore not be assumed to have an Orange Book listing without a product-specific FDA record (FDA, 2025).

Does this patent create biosimilar or generic risk?

Biosimilar risk

There is no direct biosimilar relevance. Biosimilar applications concern biological products, while these claims cover inhaler hardware. The patent does not claim a biologic, antigen, protein sequence, cell line, manufacturing process or biologic formulation.

Generic risk

The patent could historically have affected generic dry-powder inhalers if the reference and proposed generic products used the claimed reservoir-and-cup mechanism. The main generic risk points were:

Use of a hinged cover as the dose actuator;
A bulk reservoir with a dispensing port;
A movable metering cup;
A ratchet-controlled yoke;
Two cover-mounted cams;
A three-position opening and closing sequence.

A generic manufacturer using unit-dose blisters, capsules, a rotary dosing disk, a sliding shutter or a different actuation sequence would have had a stronger noninfringement position.

Because the patent term has likely ended, it should not independently prevent a 2026 generic launch. Related patents, trademarks, regulatory exclusivities, formulation patents or patents covering a commercial inhaler product could still matter.

What patent landscape surrounds this technology?

The relevant landscape has five technical clusters.

Landscape cluster	Typical protected subject matter	Relationship to U.S. 6,718,972
Reservoir metering	Bulk powder reservoir, dose cup, shutters and valves	Directly overlaps the core claim concept
Cover-actuated mechanisms	Hinges, cams, yokes, ratchets and reset mechanisms	Directly relevant to claim 1
Powder dispersion	Swirl chambers, vanes, grids and impaction surfaces	Relevant to claims 7 and 8
Dose counting	Ribbon, spool, pawl, rotary disk and electronic counters	Relevant to claim 9
Reservoir pressure control	Bellows, vents, seals and pressure-relief conduits	Relevant to claims 10, 19 and 20

The strongest historical design-around routes were to change the dose-transfer architecture rather than merely alter the cam geometry. A competing device could use a blister strip, a capsule piercer, a rotating dose wheel, a sliding metering chamber or an electronically controlled valve.

How strong is the patent estate for enforcement?

The patent is strongest against a product that copies the entire mechanical sequence. Claim 1 has substantial structural detail, which limits coverage but provides a relatively concrete infringement test.

Strengths

The claim combines dosing, actuation and reset functions in one integrated mechanism.
The two-cam and three-position sequence is technically distinctive.
Claims 13 and 14 give a detailed positional relationship for the cam surfaces.
Claims 16 and 17 address practical ratchet-reset implementations.
Claim 10 covers a specialized pressure-relief and sealing arrangement.

Weaknesses

Claim 1 requires numerous elements in combination.
The claim depends on a particular cover-driven yoke architecture.
Many alternative inhaler designs can avoid the claimed cup-and-ratchet sequence.
Claims 7 through 10 and 19 through 20 are narrow subcombinations.
The patent's ordinary term has likely expired.

The patent would have been more valuable as a design-control and licensing asset during its enforceable term than as a broad platform patent covering all dry-powder inhalers.

What litigation and settlement issues should be reviewed?

No litigation or settlement conclusion can be made from the claims alone. A complete historical review should examine:

USPTO Patent Center for reexamination, reissue, maintenance and prosecution events.
PACER and court dockets for infringement complaints, declaratory judgments and settlements.
Google Patents and WIPO records for continuations and foreign family members.
FDA product records for inhalers incorporating the claimed architecture.
Orange Book listings for any approved drug product associated with the device.

The key litigation issue would have been claim construction around "yoke," "cup," "ratchet," "cam surface," "three positions" and the requirement that the cover opening and closing produce the stated sequence.

How does U.S. Patent 6,718,972 compare with competing inhaler patent strategies?

Strategy	Typical claim focus	Relative position against U.S. 6,718,972
Bulk-reservoir inhaler	Metering chamber and reservoir interface	Potentially close
Blister inhaler	Foil strip, blister indexing and puncture	Often a design-around
Capsule inhaler	Capsule holder, piercing and airflow	Generally outside the claimed cup architecture
Rotary dose inhaler	Rotating disk or drum	May avoid the yoke-and-cam sequence
Passive DPI	Airflow path and powder dispersion	Relevant only if it also uses the claimed mechanical dosing system
Pressurized inhaler	Canister, valve and actuator	Usually outside the dry-powder reservoir claims
Electronic inhaler	Sensor, controller and powered metering	Usually avoids the mechanical limitations

Key Takeaways

Claim 1 covers a specific cover-actuated, reservoir-fed metering mechanism.
The critical elements are the movable cup, ratchet-controlled yoke, two cams, three cam surfaces and sequential three-position movement.
Claims 7 and 8 protect a specialized swirl-chamber de-agglomerator.
Claim 9 covers a ribbon-and-spool dose counter driven by a yoke pawl.
Claim 10 covers a pressure-relief and dual-sealing cup arrangement.
Claims 19 and 20 cover bellows-assisted reservoir pressurization.
The patent is a device patent and does not protect an active ingredient or therapeutic indication.
It has no direct biosimilar relevance.
Its ordinary enforceable term likely ended around 2020, subject to the official USPTO term calculation.
Current freedom-to-operate analysis must focus on continuation patents, related family members, formulation patents, method-of-use patents, trademarks and regulatory exclusivities.

Frequently Asked Questions

Can a generic inhaler infringe U.S. Patent 6,718,972 without using the same drug?

Yes. The claims are directed to inhaler structure and operation, not to a particular active ingredient. A different drug could still be relevant if the inhaler used every limitation of an asserted claim.

Does claim 1 require the inhaler to contain a dose counter?

No. The dose counter appears in claim 9. A device can fall within claim 1 without satisfying claim 9.

Does claim 1 require a bellows?

No. Bellows are added by claims 19 and 20. They are not required by the independent claim.

Can a blister-based dry-powder inhaler fall within claim 1?

Usually, a blister-based device would avoid the reservoir-and-movable-cup limitations, but the result depends on the actual structure. Claim analysis must compare each element rather than rely on the product category.

What is the most important design-around feature?

Replacing the reservoir, movable cup, ratchet and three-position yoke sequence with a materially different dose-transfer system is generally more effective than making minor changes to the cam profile.

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	028746	⤷ Start Trial
Argentina	028747	⤷ Start Trial
Argentina	064449	⤷ Start Trial
Austria	281861	⤷ Start Trial
Austria	415994	⤷ Start Trial
Austria	460955	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 6,718,972

Summary for Patent: 6,718,972