United States Patent 9,011,926 (Method for Centrifugal Fluidized Bed Granulation): Claim Scope, Likely Claim Interpretation, and US Patent Landscape
United States Patent 9,011,926 is directed to a specific centrifugal fluidized bed granulation process for active pharmaceutical ingredients, defined by quantitative process parameters: (i) spraying/dusting speed per 1 g of cores, (ii) use of a binder liquid while applying the API-containing spraying/dusting material, and (iii) a minimum total feeding weight per unit area for the centrifugal fluidized bed coating granulation machine. Dependent claims narrow key numerical ranges, and the patent also claims the resulting granules.
What does US Patent 9,011,926 claim and how broad is the method scope?
Claim 1 is the independent method claim. It covers a centrifugal fluidized bed granulation method for granules of an API comprising biologically active substance, with the following required elements:
Core limitations in Claim 1
-
Equipment/process type
- “Centrifugal fluidized bed granulation method”
- “centrifugal fluidized bed coating granulation machine”
-
Two-step material application with binder
- “spraying or dusting” an API-containing material onto cores
- while spraying/dusting, “spraying binder liquid to cores”
-
Quantitative API application rate
- Spraying/dusting speed of the API-containing material:
- “about 90 mg/min or more per 1 g of cores”
-
Quantitative total feed per unit area
- “total feeding weight per unit area” for the centrifugal fluidized bed coating granulation machine:
- “about 1.5 g/cm2 or more”
Breathing room in Claim 1
Claim 1 is structured around hard numeric floors (>= about 90 mg/min per 1 g cores; >= about 1.5 g/cm2). It does not recite:
- specific solvents, excipients, or binder chemistry
- a particular particle size distribution of cores or granules
- specific drying conditions (except the implicit centrifugal fluidized bed context)
As a result, the scope is broad on “what binder” and “what API-containing material” as long as it satisfies the defined process parameters and method structure.
Material role: “spraying or dusting material containing… biologically active substance”
The claim language treats the sprayed/dusted material as containing the API. That typically covers:
- API directly
- API mixed with excipients that are included in the sprayed/dusted formulation
- API in a powder (dusting) or liquid/solution/suspension (spraying)
Granule product coverage in Claim 5
Claim 5 depends on Claim 1 and covers:
- “granule obtained by the granulation method according to claim 1”
This is an indirect product-by-process style claim (US practice often treats such product-by-process claims as product-limited, but enforceability depends on whether the granules are distinguishable by structure, properties, or process-linked features).
How does each dependent claim narrow the numeric ranges?
Claim 2
- Spraying/dusting speed of API-containing material per 1 g cores:
- “about 90 to about 250 mg/min”
Practical effect: Claim 2 narrows the upper bound and helps convert a broad method claim into a more easily targeted infringement window.
Claim 3
- Ratio definition:
- (spraying/dusting speed per 1 g cores)/(linear velocity) is:
- “from about 0.27 to about 2”
Practical effect: Claim 3 adds an additional constraint tied to machine linear velocity, making infringement depend on how the accused process defines and measures linear velocity and whether the ratio falls within the claimed band.
Claim 4
- Total feeding weight per unit area:
- “about 1.5 to about 6 g/cm2”
Practical effect: Claim 4 narrows the total feed parameter to a second numeric envelope.
Claim 5
- Granule obtained by the method of Claim 1.
Practical effect: Product coverage is anchored to at least Claim 1’s numeric thresholds. If a process practices the method outside the floors of Claim 1, Claim 5 likely fails.
What measurements matter for infringement: mg/min per 1 g cores, g/cm2, and linear velocity?
In infringement analysis, the key is whether the accused process can be shown to meet the claim-defined parameters.
1) “spraying/dusting speed … mg/min per 1 g of cores”
This parameter is likely operationalized as:
- mass flow rate of API-containing spray/dust (mg/min) normalized by amount of cores (g) present/treated
In litigation terms: the factual record would need:
- dosing rate of the API-containing material
- core charge mass basis
- a measurement or calculation method used in production
2) “total feeding weight per unit area … g/cm2”
This implies that the centrifugal fluidized bed coating granulation machine has a defined “unit area” element used to normalize feed weight (commonly linked to equipment-specific dimensions).
In litigation terms: success often turns on:
- what “unit area” corresponds to on the accused machine
- the time period over which “total feeding weight” is summed
- whether “total feeding weight” includes only the API-containing spray/dust or additional feeds
3) “linear velocity”
Claim 3 creates an extra dependency on:
- how linear velocity is defined (equipment-specific)
- how it is measured or derived from machine settings
In practice, linear velocity is typically tied to rotation and/or air flow conditions in centrifugal fluidized bed systems. If a competitor uses a different bed design or defines linear velocity differently, claim 3 can become a dispute point.
What US claim construction issues are most likely for US 9,011,926?
“about” ranges
All numeric terms use “about,” which courts generally treat as permitting some tolerance but not open-ended. The practical infringement threshold depends on the specification’s guidance and prosecution history, if any.
“spraying or dusting”
Two alternatives are expressly covered:
- spraying (liquid application)
- dusting (powder application)
So a design-around that switches spray to dust likely does not avoid coverage if dosing and total feed meet the same parameter thresholds.
“cores” and “granules”
The claim assumes an initial seed/core bed and formation of granules. Competitors using a different starting material (for example, pre-agglomerated pellets) may still be “cores” if they function as the seed material in centrifugal fluidized bed granulation.
Product-by-process in Claim 5
For Claim 5, enforcement depends on whether the product can be distinguished based on:
- granule characteristics tied to the process parameters
- or evidence that accused granules are made by the claimed method
What patents protect the same centrifugal fluidized bed granulation strategy in the US?
A robust landscape for this technology typically clusters into these families:
- Centrifugal fluidized bed granulation/coating parameter control
- API application rate, atomization, and binder spraying in centrifugal systems
- Feeding rate normalization tied to equipment geometry
- Granule properties resulting from centrifugal granulation methods
However, because only the claims of US 9,011,926 are provided here and no bibliographic data (assignee, filing date, CPC/IPC, related publication number, specification details, or cited references) are included, a complete and accurate cross-patent identification cannot be produced.
Which other patent estates likely compete with US 9,011,926 (and where would they overlap)?
Without the patent’s full text (specification) or its prosecution/citation data, any attempt to enumerate specific US-family competitors would risk inaccuracy.
What can be stated from the claim structure alone is the most likely overlap zone:
- granulation machines using centrifugal fluidized beds (commercially, these are often associated with equipment vendors whose systems enable dusting/spraying and binder liquid addition)
- processes using quantitative application rates and machine-parameter-linked dosing
The “hard numbers” in Claim 1 (>= about 90 mg/min per 1 g cores; >= about 1.5 g/cm2) are the most likely features copied or designed around in competing filings.
When does US 9,011,926 lose exclusivity?
No filing date, priority date, patent term adjustments (PTA), or expiry data is provided with the claim text. Without those, an exclusivity timeline cannot be calculated accurately.
Can a generic or competitor enter during the patent term via Paragraph IV or design-around?
The patent claims a method of granulation and a product obtained by that method. In the US, generic entry typically triggers patent litigation if patents are listed for the relevant drug in the Orange Book and if the asserted claims read on the generic’s activities.
Because the relevant drug product and Orange Book listing are not provided here, the Paragraph IV risk profile cannot be mapped accurately.
What is the likely litigation and settlement posture for this kind of process patent?
Process patents tied to manufacturing steps are frequently asserted in:
- discovery disputes over whether accused parameters meet the claimed windows
- experts’ measurement and calculation methodology disputes (mg/min per g cores, g/cm2, linear velocity)
- product-by-process evidence disputes for Claim 5
No docket, court, or settlement record is provided here, so the litigation landscape cannot be stated.
How strong is the enforceability of US 9,011,926 based on claim structure alone?
Strength indicators from the claims:
- Quantitative constraints are explicit in the independent claim.
- Dependent claims add alternate numeric windows and a ratio involving linear velocity.
Vulnerability indicators from the claims:
- The breadth on binder identity and API excipient formulation could raise prior-art combinations issues, depending on what the specification says.
- “about” range interpretations can be fact-intensive.
- Claim 5 depends on Claim 1 method practice; if granules can be characterized differently, competitors can attempt to argue product non-equivalence.
What design-arounds are most plausible against this claim set?
Based only on the numeric limitations in Claim 1:
-
Lower API-containing spraying/dusting speed below about 90 mg/min per 1 g cores
- This targets the primary floor.
-
Lower total feeding weight per unit area below about 1.5 g/cm2
- This targets the second primary floor.
-
Avoid satisfying the Claim 3 ratio window
- If a competitor operates outside 0.27 to 2 for (spraying/dusting speed per 1 g cores)/(linear velocity), Claim 3 is avoided, though Claim 1 can still read if Claim 1 floors are met.
-
Use a centrifugal process variant that does not meet the defined “total feeding weight per unit area” normalization
- If measurement definitions differ, infringement analysis becomes contested.
Key Takeaways
- US 9,011,926 Claim 1 covers a centrifugal fluidized bed granulation method with two required numeric thresholds: API spraying/dusting speed >= about 90 mg/min per 1 g cores and total feeding weight >= about 1.5 g/cm2.
- Dependent claims narrow scope to: API spraying/dusting speed about 90 to about 250 mg/min (Claim 2), a dosing/linear-velocity ratio about 0.27 to about 2 (Claim 3), and total feeding weight per unit area about 1.5 to about 6 g/cm2 (Claim 4).
- Claim 5 extends coverage to granules obtained by practicing Claim 1.
- Enforcement hinges on manufacturing evidence: dosing rate calculations, normalization basis for cores and equipment area, and measurement/derivation of linear velocity.
- A complete US patent landscape (other family members, competitors, expiries, litigation) cannot be established from the claims text alone.
FAQs
What does “spraying or dusting speed … mg/min per 1 g of cores” mean in practice?
It is a mass application rate of the API-containing spray/dust, expressed in mg/min and normalized to the core mass basis (g) used in the batch or processing window.
How could a competitor avoid Claim 1 without changing the equipment?
By operating at an API spraying/dusting speed below the claimed threshold or reducing total feeding weight per unit area below the claimed minimum, while still performing centrifugal fluidized bed granulation.
Does Claim 5 give product protection even if the method is not followed exactly?
Claim 5 is tied to granules “obtained by” the Claim 1 method. If the accused granulation does not meet Claim 1’s quantitative requirements, Claim 5 is at risk.
Is Claim 3 an additional independent constraint or an optional narrowing?
It is a dependent narrowing: it applies only if Claim 1 is satisfied and the additional ratio involving linear velocity falls within the claimed band.
Are binder formulations relevant to infringement of US 9,011,926?
The claims require spraying binder liquid, but do not specify binder chemistry. Binder identity may matter for validity/prior art, but infringement depends primarily on meeting the process and quantitative limitations.
References (APA)
- United States Patent 9,011,926. Claims provided in prompt.
