United States Patent 5,061,494: Scope, Claim Architecture, and US Patent Landscape for a Tri-Scored Tablet

United States Patent 5,061,494 covers a tri-scored oral tablet with a specific mechanical score-and-break geometry that enables user-directed sequential splitting: first into two halves along a central longitudinal break, then into four quarters through top-and-bottom breaking grooves that align with paired concavities on the bottom surface.

What is the invention’s core scope (technical and functional)?

1) Structural backbone: elongated tablet + matched bottom concavities

Claim 1 requires an elongated tablet body where length > width, with flat top surface and two concavities in the bottom surface that are:

Equal in size
Each has parallel major and minor axes
Each concavity has a smooth and uninterrupted arcuate surface
Each arcuate surface extends:
- between the opposite longitudinal ends of the tablet body
- and across a longitudinally central part of the tablet
The tablet has thicker dimensioned portions at both longitudinal ends and at the longitudinally central part, relative to the apex thickness at each concavity

This combination ties the geometry of the bottom concavities to the break behavior.

2) Score-and-break system: aligned grooves across top and bottom

Claim 1 requires aligned breaking grooves formed in top and bottom at:

both concavities (so there are grooves at the concavity apex locations)
and between the concavities at the longitudinally central part

Each breaking groove:

extends laterally across the width of the tablet at:
- each concavity apex
- and the central part

The functional tie-in is explicit: the grooves are shaped to fracture at specific locations when force is applied.

3) User-directed fracture sequence (two-stage division)

Claim 1 is not just a geometric claim; it requires a specific splitting workflow:

User grasps both ends (forefinger/thumb on each hand)
Force is applied to effect fracture along the groove at the longitudinally central part
User then stacks the two half sections so:
- concavities face one another
- thicker end regions engage
User applies a compressive force to the midpoint of the stacked halves
This causes simultaneous fracture of each half along grooves at the concavity apexes
Result: each half becomes two quarter sections, yielding four quarters total

4) Dose distribution requirement

Claim 1 further limits to dose uniformity:

each quarter section contains within ±15% by weight of a prescribed limit of pharmacological agent

This makes the claim cover a tablet that breaks into portions that are not merely divisible, but dose-close to target.

How do dependent claims narrow scope?

Claim 2: Perimetrical central body geometry + groove depths and thickness relationships

Claim 2 narrows and specifies multiple geometric dimensions:

tablet includes an elongated central body part of:
- finite and uniform thickness
has a smooth and uninterrupted perimetrical surface extending parallel to a theoretical line perpendicular to the top surface, passing through the geometric center of the tablet
each end concavity creates a region defined by a surface part and a concavity depth condition:
- depth of each concavity is less than the highest height dimension of the surface parts
groove depth bounds:
- breaking grooves in concavities and longitudinally central bottom extend from the concavity apex to the bottom surface of the central body part
- breaking grooves in top surface depth extends approximately one fourth to one half the distance between:
- top surface and
- the top surface of the central body part

This claim is a dimensional envelope around the scoring system.

Claim 3: Further constrains top-groove depth

Claim 3 tightens Claim 2 by specifying:

breaking grooves in the top surface extend one third the distance between:
- the top surface and
- the top surface of the central body part

Claim 4: Axis alignment of concavities

Claim 4 requires:

the major axis of each concavity extends parallel to the longitudinal axis of the elongated tablet body

This limits concavity orientation.

What is the claim set covering in legal terms? (scope mapping)

A. Device claim with a method-of-use-like fracture sequence

Although framed as a “tri-scored drug tablet,” Claim 1 includes a user action sequence that operationally defines the structural adequacy. In practice, infringement arguments typically focus on whether the accused tablet, when acted on in the claimed manner (stacking orientation and force application), fractures into the claimed quarters with required dose uniformity.

B. Claim requires a specific “interaction” between concavities and grooves

The alignment requirement matters:

concavities exist on the bottom
grooves exist on both top and bottom
grooves align at:
- concavity apex locations
- the central longitudinal part
the stacking alignment (concavities facing, thicker ends engaged) is part of the required division sequence

That “stacking engagement” reduces the scope to tablets engineered for sequential fracture mechanics rather than merely any scored tablet.

C. Quantified dose uniformity ties breakability to pharmaceutical content

The ±15% by-weight dose constraint narrows coverage to tablets designed so that each quarter contains pharmacological agent within the stated deviation.

Where does this sit in the US scored-tablet patent landscape?

Landscape anchor: general scored tablet splitting patents

The scored-tablet field in the US has long included patents covering tablets with grooves or multiple scores intended for segmentation into equal or dose-controlled portions.

However, 5,061,494 is distinguishable by combining:

tri-scoring architecture (multiple break lines enabling four parts through a two-step workflow)
bottom arcuate concavities paired symmetrically
groove alignment across top and bottom
explicit stacking orientation and simultaneous fracture behavior
a quantified ±15% by weight content constraint per quarter

Practical implication for freedom-to-operate (FTO) screening

For FTO, the relevant “risk buckets” are patents that claim one or more of the following:

Multi-stage segmentation (e.g., split into halves then quarters)
Paired concavity-driven break control (not only straight grooves)
Top-and-bottom groove pairing aligned with concavity apexes
Concavity orientation parameters and groove depth ratios (one quarter to one half; one third)
Dose uniformity thresholds after breaking

In many generic scored-tablet patents, claims focus on the presence of break grooves. 5,061,494’s stronger differentiator is the structured fracture workflow plus geometry constraints.

Claim-to-landscape differentiation matrix

Feature required by 5,061,494	What it excludes in many “standard scored” tablet patents
Two symmetric bottom concavities with arcuate uninterrupted surface	Tablets with only linear grooves without concavity-based stress shaping
Aligned top and bottom breaking grooves crossing concavity apexes and central part	Tablets with grooves on one surface only
Two-step user fracture: half-then-quarter with stacking orientation	Tablets designed only to break once into two pieces
Grooves extend laterally across tablet width at apexes and mid-part	Designs where break lines are partial, non-lateral, or rely on tablet crumbling
±15% by weight pharmacological content per quarter	Patents that do not quantify dose distribution after splitting
Specific depth relationships (Claim 2/3): top grooves one quarter to one half; or specifically one third	Generic scoring depth without defined ratios

Operational scope: what “counts” as infringement under claim logic?

What an accused tablet must match (from Claim 1)

An accused product must include, at minimum, the combination of:

elongated tablet body with flat top
two bottom concavities equal size with parallel axes and arcuate uninterrupted surfaces
thicker end and central portions relative to concavity apex thickness
aligned breaking grooves:
- at both concavities and at the longitudinally central part
- present on both top and bottom surfaces
grooves extending laterally across width at each apex and at the central break line
fracture behavior consistent with:
- first break into two halves at central groove
- stacking concavity-face-to-face and thick-end engagement
- compressing midpoint to create simultaneous fractures at concavity apex grooves
each resulting quarter contains pharmacological agent within ±15% by weight of prescribed limit

What dependent claims further lock down

Claim 2 adds specific central body geometry and groove depth bounds
Claim 3 fixes top groove depth at one third of a defined distance
Claim 4 fixes major axis orientation parallel to tablet longitudinal axis

Key patent landscape implications for investors and R&D teams

1) Design-around opportunities exist where the claim’s “system” collapses

The tightest design risk comes from replicating the whole system: concavities + aligned top/bottom grooves + stacking-defined second fracture.

Design-around directions often involve removing one of the claim’s required linkages:

eliminating top-surface groove alignment
breaking only once into halves (no quarters via second stacking compression)
replacing arcuate concavities with different stress features
changing dose uniformity approach such that quarter-content does not meet the ±15% by weight limit

2) Manufacturing and QC become part of the infringement question

Because the claim ties the broken quarters to pharmacological content within ±15% by weight, a product’s blend uniformity and scoring mechanics after fracture become relevant.

3) Claim depth ratios create measurable engineering constraints

The explicit depth relationships in Claims 2 and 3 limit how loosely a scored tablet can be made while still falling within the narrower claim scope.

Key Takeaways

US 5,061,494 claims a tri-scored elongated tablet engineered for a two-step user fracture sequence: halves first, then quarters via stacking with concavities facing and thick ends engaged.
The claim’s core novelty is the combination of paired bottom concavities plus aligned top-and-bottom breaking grooves at concavity apexes and a central groove, yielding simultaneous quarter fractures.
Scope narrows further through specific geometric depth constraints (top groove depth ratios) and dose uniformity of each quarter within ±15% by weight.
In the US scored-tablet landscape, 5,061,494 is more likely to overlap with patents claiming multi-part break mechanics and dose-controlled segmentation, rather than generic single-line score break patents.
For FTO, the highest risk is replicating the whole “system”: concavity-plus-aligned-groove architecture plus two-step splitting workflow with quantified quarter-dose uniformity.

FAQs

What does “tri-scored” mean in this patent’s context?

It refers to the tablet having multiple breaking/groove features arranged so the user can split the tablet in stages, ultimately producing quarters through a central break followed by concavity-apex breaks.

Is this patent only about grooves, or does it require concavities too?

Claim 1 requires two concavities in the bottom surface plus aligned breaking grooves at those concavities and at the longitudinally central part.

Does the patent require a specific user stacking step?

Yes. Claim 1 requires the user to split into two halves, then stack them with concavities facing and thicker end portions engaged before applying compressive force.

How strict is the dose uniformity requirement?

Claim 1 requires each quarter to contain pharmacological agent within ±15% by weight of a prescribed limit.

Which dependent claims are most limiting on design parameters?

Claims 2 and 3 constrain central body geometry and breaking groove depths, while Claim 4 fixes the concavity major-axis orientation relative to the tablet’s longitudinal axis.

References

[1] US Patent 5,061,494. “Tri-scored drug tablet.” Claims 1-4 (as provided).

Details for Patent: 5,061,494

Summary for Patent: 5,061,494