Polycorp Ltd.

20 patents currently held · Updated Nov 14, 2026

Held is read from USPTO's recorded assignments; a transfer never recorded there does not appear.

Ending by 2030

Dec 2029

Next term end

When these terms end

5 yrs10 yrs20 yrs

Held patents by the year their term ends

20262027202820292030203120322033203420352036203720382039204020412042204320442045

Fee deadlines

Maintenance fees fall due 3.5, 7.5 and 11.5 years after grant. A missed fee ends a patent at the end of the six month grace period that follows, not on the due date.

1 fee due Dec 6, 2026
The maintenance fee for Split Pulp Chamber Insert Assembly (US 11,666,923) comes due Dec 6, 2026. Unpaid by Jun 7, 2027, it lapses early.
1 fee due Feb 6, 2027
The maintenance fee for Rail Assembly (US 10,370,798) comes due Feb 6, 2027. Unpaid by Aug 6, 2027, it lapses early.
1 fee due Mar 12, 2027
The maintenance fee for Anti-Plugging Discharge Grates (US 11,752,503) comes due Mar 12, 2027. Unpaid by Sep 13, 2027, it lapses early.
2 fees due Apr 1 to 29, 2027 · next Apr 1
1 fee due May 26, 2027
The maintenance fee for Special Trackwork Assembly (US 10,487,456) comes due May 26, 2027. Unpaid by Nov 26, 2027, it lapses early.
1 fee due Sep 22, 2027
The maintenance fee for Discharge Grate Assembly (US 9,289,775) comes due Sep 22, 2027. Unpaid by Mar 22, 2028, it lapses early.

Which patents, and when each one lapses · Pro

Recent changes

Nothing was recorded against this company's patents in the last 90 days.

Patents held now

Soonest term end first. Each date below is computed on that patent's own page, which shows the rule, the adjustments and the fee history it was derived from.

Patent	Title	Status	Expires	Confidence
US 8,360,350	Discharge End Liner In force Term ends Dec 10, 2029 · High confidence	In force	Term ends Dec 10, 2029	High confidence
US 8,172,158	Flangeway Former and Rail Boot System In force Term ends Mar 8, 2030 · High confidence	In force	Term ends Mar 8, 2030	High confidence
US 8,100,342	Shallow Flangeway Rail Seal In force Term ends Jun 30, 2030 · High confidence	In force	Term ends Jun 30, 2030	High confidence
US 8,245,950	Removable Rail Seal In force Term ends Oct 22, 2030 · High confidence	In force	Term ends Oct 22, 2030	High confidence
US 8,714,462	Special Track Assembly and Methods of Making Same In force Term ends Aug 2, 2031 · High confidence	In force	Term ends Aug 2, 2031	High confidence
US 8,622,330	Mill Liner Assembly In force Term ends Apr 14, 2032 · High confidence	In force	Term ends Apr 14, 2032	High confidence
US 9,289,775	Discharge Grate Assembly In force Term ends Feb 20, 2034 · High confidence	In force	Term ends Feb 20, 2034	High confidence
US 9,617,688	Rail Assembly In force Term ends Aug 24, 2034 · High confidence	In force	Term ends Aug 24, 2034	High confidence
US 10,370,798	Rail Assembly In force Term ends Aug 24, 2034 · High confidence	In force	Term ends Aug 24, 2034	High confidence
US 10,427,164	Discharge End Wall Inserts In force Term ends Oct 21, 2036 · High confidence	In force	Term ends Oct 21, 2036	High confidence

10 of 20 patents shown.

Pro members see all 20.

Pro members: see all 20 patents

Also on record, not counted in the 20: 1 lapsed for an unpaid fee · 3 ended at full term. List them

Sources and methods

Compiled from the USPTO record, grants, published applications and recorded assignments, not yet reviewed by hand. How this record was built

Computed patent terms end on the dates shown. Related patents and pending applications may cover overlapping subject matter.

Export every term end as CSV · Pro

Published applications

US patent applications published under this name that have not become patents. An application is published about eighteen months after its earliest filing; one that has not been published is in no public record.

4 abandoned

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