United States Patent 10,058,440: Claims and US Patent Landscape for a Knitted-Cover, Sliding-Loop Carotid Stent Assembly
What does US 10,058,440 claim in practical terms?
US Patent 10,058,440 claims a carotid stent assembly that combines: (i) a self-expanding metallic support and (ii) a knitted polymer cover that is only attached to the metal at the distal and proximal struts through sliding connections defined by flexible loops made from a single polymer fiber. The cover is designed to block larger debris while still enabling endothelial growth through apertures in the combined metal-plus-cover system.
Claim 1: core combination (claim scope anchor)
Claim 1 requires, together:
- Self-expanding support element for carotid placement
- Distal and proximal ends
- Metal struts, including distal strut and proximal strut
- Expansion from retracted to expanded state
- Knitted cover disposed over the exterior of the support
- Extends along the entire length
- Attached to the support only at:
- the distal strut at the distal end of the knitted cover, and
- the proximal strut at the proximal end of the knitted cover
- Knitted cover material:
- Single polymer fiber with diameter ≥ 40 nm to 30 microns
- Combined apertures sized for debris blocking:
- Apertures in the support element + knitted cover together are 20 microns to <100 microns
- Purpose stated: block larger debris when expanded in the carotid artery
- Sliding attachment structure:
- Knitted cover and metal are attached by sliding connections
- Sliding connections comprise one or more flexible loops formed from the single polymer fiber
- Loops are formed in the knitted cover and attached to a flexible portion of the support
- First flexible loop:
- attached to the distal strut
- slides only along the distal strut
- Second flexible loop:
- attached to the proximal strut
- slides only along the proximal strut
- Result: permits radial sliding of knitted cover relative to the support at distal and proximal struts
This is a constrained mechanical architecture: end-to-end knitted cover with end-point-only attachment, plus loop-defined sliding at those attachment points, plus specific pore/aperture size targets for debris blocking and endothelialization.
Dependent claims: the numeric and pharmacologic expansion
Claims 2 to 30 add narrower ranges and optional layers, including drug-elution configurations.
Fiber diameter ranges
- Claim 2: single polymer fiber 10 to 30 microns.
Biology-oriented pore and cell growth
- Claim 3: fiber and apertures sized to encourage endothelial cell growth through the assembly.
Mechanical accommodation during expansion
- Claim 4: knitted cover has slack to enable expansion upon radial expansion of the support.
Biostability/resorbability
- Claim 5: fiber is biodegradable or bioresorbable.
Cover coverage ratio (porosity by geometry)
- Claim 6: coverage area <25% of exterior support area.
- Claim 7: coverage area <20% of exterior support area.
- Claim 8: approximate aperture size 20 to 50 microns.
Polymer options
- Claim 9: fiber can be among listed classes (thermoplastics, polyolefin elastomers, thermosets, polyester, polyurethane, polyfluoropolymer, nylon).
- Claim 10: includes specific polymers and blends, including PP, PET, nylon 6/6, PTFE, PVA, polyurethane, PLLA, etc.
Knitting structure density
- Claim 11: knitted cover comprises 20 to 50 courses per cm.
Coatings and drug elution
- Claim 12: optional coating on knitted cover and/or metal struts.
- Claim 13: coating comprises polymer or hyaluronic acid/hyaluronan.
- Claim 14: active pharmaceutical agent can be eluted from cover and/or coating.
- Claims 15-17: time-released over 2 hours to months, at 1 to 200 micrograms/cm².
- Claims 18 and 19: active agent includes zolimus/zotarolimus/sirolimus/tacrolimus/everolimus plus optional additional agent classes (anti-proliferative, antithrombotic, growth factor inhibitor, steroid/corticosteroid, statin) with extensive exemplar lists.
- Claims 20-25: parallel drug-elution configurations where agent is eluted from support element or coating (not only knitted cover), with substantially similar active agent definitions.
Expanded mechanical refinement
- Claim 26: loop tension controlled by tightening; distal/proximal struts have zigzag pattern with distal points and proximal points; loops attach to specific points; first loop travels between distal and proximal points on distal strut; second loop travels between points on proximal strut.
Method claims
- Claim 27: method of stenting a carotid artery:
- apply stent assembly of claim 1
- expand in situ to trap debris
- Claims 28-29: expansion range 2 to 8 mm; reduces thrombosis compared to stent lacking knitted cover.
- Claim 30: method treating embolic showers at catheter insertion using the stent and in situ expansion.
What is the infringement theory implied by these claims?
1) The “knitted cover” and “only-attached-at ends” architecture is the infringement fulcrum
To infringe claim 1, an accused device must meet the combination of:
- a knitted polymer cover over a self-expanding metal carotid stent
- attachment only at distal and proximal struts
- sliding connections defined by flexible loops formed from a single polymer fiber
- sliding restricted such that:
- loop1 slides along distal strut only
- loop2 slides along proximal strut only
- aperture sizing and fiber diameter constraints
A design-around that keeps a knitted cover but changes attachment to include additional connection points (mid-stent tie points, circumferential sutures, radial staples, or multiple sliding anchor points) risks eliminating the “attached together only at the distal strut... and the proximal strut...” limitation.
2) Aperture and coverage limits create additional claim barriers
Even if a competitor matches the mechanical architecture, they must approximate the claim’s combined aperture and coverage requirements:
- apertures sized 20 to <100 microns
- optional but narrow dependent limitations:
- coverage area <25% or <20%
- aperture 20 to 50 microns
- fiber diameter 10 to 30 microns
- knitting density 20 to 50 courses/cm
Because claim 1 uses “apertures sized 20 microns to smaller than 100 microns,” an accused device’s manufacturing variability and characterization method can matter materially to whether pore size distribution falls within that window.
3) Drug-eluting variants are dependent, so a generic cover-only device may avoid narrower drug claims
Drug claims (14-25) require additional structural and functional features: coatings/agent elution with time-release and dose ranges and, in dependent claims, specific drug species. A competitor making a non-drug device could still be exposed to claim 1 and method 27-30, but would likely reduce exposure to drug-specific dependent claims.
Where does the claim likely sit within the broader carotid embolic protection and stent cover landscape?
The claimed device sits at the intersection of:
- carotid stents (self-expanding metal scaffolds),
- embolic debris management (filtering larger debris),
- covered stents / flow-occluding barriers,
- porous media allowing endothelialization, and
- drug-eluting polymer layers.
US 10,058,440’s distinguishing points are the knitted polymer cover and the end-point-only sliding attachment by loops that accommodates radial expansion while maintaining debris-blocking aperture sizing.
Critical perspective on novelty signals in the claim set
The claim set is unusually specific on:
- single fiber diameter range
- aperture size windows (20-<100 microns; dependent 20-50)
- knitted coverage percentage thresholds (<25%, <20%)
- knitting courses per cm (20-50)
- mechanical sliding constraints (loops formed from the same single polymer fiber; loops sliding only along designated struts)
That specificity often indicates the patent is trying to carve out prior art configurations where:
- covers are attached circumferentially or fully bonded,
- pore sizes are too small (occlusion risk) or too large (debris passage),
- covers are not designed to accommodate radial expansion via controlled sliding,
- polymer fiber geometry and knitting density were not previously constrained to the same biological and mechanical targets.
Claim-by-claim pressure points (validity and design-around sensitivity)
Claim 1: likely highest-risk validity attack surface
The broadest claim is also the most internally structured: it requires all mechanical and sizing limitations simultaneously. That can help validity but increases difficulty for an accused infringer to avoid every limitation.
Potential vulnerabilities (in how examiners and courts often test such claims):
- Claim clarity and definiteness: “apertures sized 20 microns to smaller than 100 microns” can be challenged depending on how apertures are defined across the composite knitted fiber + metal strut mesh.
- Functional language tied to structure: “block larger debris” and “encourage growth of endothelial cells” may be used to interpret structural scope, creating disputes over whether pore/aperture sizing is “the same” as actual biological function.
Dependent claims: tightening that narrows design-around options
- Fiber diameter (claim 2) and polymer list (claims 9-10) narrow material-based workarounds.
- Coverage ratio (claims 6-7) and aperture size (claim 8) create quantifiable targets.
- Knitting density (claim 11) constrains manufacturing parameters.
- Slack (claim 4) and biodegradable (claim 5) are additional constraints.
For design-around, a competitor would generally target one of these dependent limitations only if claim 1 is already avoided; otherwise, avoiding claim 1 is the key step.
Drug-eluting dependent claims: an enforceability lever if a competitor markets a drug-eluting version
The extensive definition of active agents in claims 18-19 and 24-25 suggests the patentee wanted broad coverage over “z-” immunosuppressant drugs plus typical adjunct agent classes.
For infringement, this means:
- If a competitor uses those specific drug species with time-release elution and compatible dosing and coverage location, exposure rises quickly.
- If a competitor uses different drugs, or a different time-release profile not within “2 hours to a plurality of months,” drug dependent claim risk decreases, while claim 1 still remains.
US patent landscape: how the claim likely competes (and overlaps)
A complete competitive landscape requires the cited priority chain, assignee, prosecution history, and the full family set for US 10,058,440, plus identification of earlier issued US patents and published applications covering:
- knitted or woven polymer covers on carotid stents,
- self-expanding metallic stents with porous coverings intended to filter emboli,
- sliding or end-tethered coverings,
- polymer fiber diameter + pore size engineering for endothelialization,
- drug-eluting carotid stent covers.
Those elements are necessary to map citation density, anticipate obviousness combinations, and assess whether the key differentiators (knitted cover, single-fiber loops, distal/proximal-only sliding attachment, and aperture windows) are already disclosed in earlier references. Without the publication metadata for US 10,058,440 itself, the landscape mapping cannot be completed with the precision required for investment or freedom-to-operate decisions.
Critical read: what the claims say the product does (and what they may not cover)
What the claims clearly cover
- A carotid stent with a self-expanding metal scaffold.
- A knitted polymer cover spanning the stent length.
- Controlled relative motion between cover and scaffold during radial expansion through loop sliding at only distal and proximal struts.
- Composite aperture sizing targeting embolic debris blocking and endothelialization.
- Optional coatings/drug elution with specific drug families and release/dose windows.
What the claims do not clearly cover (as written)
- A fully bonded or fully circumferentially attached cover across multiple points along the length (claim 1 says attachment only at distal and proximal struts).
- Covers that are not “knitted” (claims require knitted cover; a woven mesh could be outside scope depending on claim construction).
- Covers made from multiple fiber types or multiple fiber diameters if they no longer satisfy “single polymer fiber” and its diameter constraints.
- Non-self-expanding scaffolds or balloon-expandable scaffolds.
Key takeaways
- US 10,058,440 claim 1 is a composite mechanical and structural invention: a carotid self-expanding metal stent plus a knitted polymer cover attached only at distal and proximal struts using single-fiber flexible loops that slide only along those struts, while delivering 20 to <100 micron composite apertures for debris blocking and endothelialization.
- Design-around is most feasible by breaking the attachment architecture (add extra attachment points, change from loop sliding limited to distal/proximal struts, or change the cover construction so it is not “knitted” or not “single polymer fiber”).
- Dependent claims add hard numerical constraints (fiber diameter 10-30 microns, coverage ratio <25% or <20%, aperture 20-50 microns, 20-50 courses/cm), creating additional barriers for partial look-alikes.
- Drug-eluting coverage is dependent and ties to specific “zolimus” class drugs plus adjunct agent categories, with dose and release windows; a non-drug version may still face exposure under claim 1 and method claims 27-30.
- A complete “critical analysis of the claims and the patent landscape” cannot be completed from the claim text alone: a landscape requires bibliographic and family data (publication, priority, assignee, cited references) to identify overlap and the likely validity battle under US §§ 102/103.
FAQs
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What is the single most important structural limitation in claim 1?
The knitted cover is attached to the support element only at the distal strut and proximal strut via sliding connections that slide only along those struts.
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Does claim 1 require drug elution?
No. Drug and coating provisions appear in dependent claims (e.g., claims 12-25).
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What numerical range governs debris filtering in claim 1?
The combined support-and-cover apertures are sized 20 microns to smaller than 100 microns.
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How narrow are the materials requirements?
Claim 1 requires a single polymer fiber; dependent claim 2 narrows fiber diameter to 10-30 microns, and claims 9-10 list specific polymer families.
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What is the intended mechanical function of the flexible loops?
They permit radial sliding of the knitted cover relative to the metal support during expansion while keeping the cover anchored at the defined distal and proximal strut locations (claims 1 and 26).
References (APA)
[1] US Patent 10,058,440, “Carotid stent assembly with knitted cover and sliding loop attachment,” claim set as provided in the user prompt.
