Collateral for a security interest recorded Jul 7, 2020 (The Toronto-Dominion Bank).

Term ends Aug 22, 2039 · High confidence

Computed 20-year base term

Held by Specialized Desanders Inc.

Filed May 29, 2018 as application 15/991,771 · Granted Jun 15, 2021

Base term plus 450 days of patent term adjustment (USPTO delay)

Today

20 years from filing

Term ends Aug 22, 2039

2018 2039

Clock starts
May 29, 2018

Term ends
Aug 22, 2039

Granted
Jun 15, 2021

base term patent term adjustment fee events Updated Nov 14, 2026 · includes USPTO assignment & status data published Nov 14, 2026 and grant & fee data published Nov 10, 2026 (weekly) · how we know

450

Days of term adjustment

Read from the USPTO patent term adjustment record, not recalculated here.

None

Terminal disclaimer

No disclaimer on this record.

1 of 3

Maintenance fees paid

Three maintenance fees fall due, at 3.5, 7.5 and 11.5 years from grant. This counts the ones the record shows paid.

Family applications on record here

Applications sharing this one's continuity chain whose file history this site holds. The family may have others.

This patent's term runs 450 days past its 20-year base term on prosecution delay. 1 of 3 maintenance fees is paid so far. Confidence: High. from the record

How we calculated this date

One row per rule, each showing its own input and what it did to the date. A step we could not verify says so instead of resolving itself.

Step	Input	Date after this step	Confidence
Base term, 20 years from filing	Clock starts May 29, 2018, when this application, 15/991,771, was filed	May 29, 2038	High confidence
Continuity chain	Every parent in the chain resolved	no change	High confidence
Patent term adjustment	+450 days, USPTO patent term adjustment record	Aug 22, 2039	High confidence
Terminal disclaimer cap	None on record	no cap applied	High confidence
Patent term extension	None on file	no change	High confidence
Fee events	1 of 3 maintenance fees paid	In force	High confidence
Computed term end	The steps above, in order	Aug 22, 2039	High confidence

This family

US 11,035,216	this patent Aug 2039	Aug 2039
US 10,967,305	In force Jun 2039	Jun 2039
US 10,807,020	In force Mar 2039	Mar 2039

The applications whose file history this site holds. The family may have others.

Assignments

Assignment documents as recorded at the USPTO, oldest first, with the reel and frame each was recorded at. A recorded assignment is a filed document, not a statement of current ownership, and the absence of a later one is not evidence that the last one still stands.

Recorded	Assignor	Assignee	Conveyance
Jun 26, 2018 Reel 46200, frame 495	Hemstock, Christopher A	Specialized Desanders Inc.	Nunc Pro Tunc Assignment
Jul 7, 2020 Reel 53139, frame 623	Specialized Desanders Inc.	The Toronto-Dominion Bank	Security Interest

Sources

Google Patents · The patent document at USPTO · Assignment records at USPTO

USPTO account required: This application in Patent Center · USPTO's maintenance fee lookup

Maintenance fee events come from USPTO's own fee records. Its fee lookup asks for the patent number and the application number.

Free plan: 3 watched companies. Pro: unlimited.

Alerts on its grants, lapses and transfers.

What's changing

Aug 2039

Term ends Aug 22, 2039. Maintenance fees still fall due before then

Note

The 450 days of patent term adjustment (USPTO delay) are read from the USPTO record, not recalculated by us

Citations

later US patents cite this one

That is above the median of utility patents granted in 2021 in our data, the only group it is compared against. How we rank

Every date shows its work: the base term, any term adjustment or extension, any disclaimer cap, and the maintenance fee record, each with a confidence tier. How this record was built

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

In force means the term is running and no lapse is on record. It is not a finding that the patent is valid.

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