Also listed on Arq Solutions, LLC, an earlier holder on the record. The recorded assignments below show how it moved.

Collateral for a security interest recorded Jan 3, 2025 (Midcap Funding IV Trust).

Term ends Nov 20, 2028 · High confidence

Computed 20-year base term

Held by Arq Solutions (Es), Inc.

Filed Oct 27, 2006 as application 11/553,849 · Granted Feb 28, 2012

Base term plus 755 days of patent term adjustment (USPTO delay)

Today

20 years from filing

Term ends Nov 20, 2028

2006 2028

Clock starts
Oct 27, 2006

Term ends
Nov 20, 2028

Granted
Feb 28, 2012

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

755

Days of term adjustment

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

None

Terminal disclaimer

No disclaimer on this record.

3 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 755 days past its 20-year base term on prosecution delay. All three maintenance fees are recorded paid; no more fees are due. 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 Oct 27, 2006, when this application, 11/553,849, was filed	Oct 27, 2026	High confidence
Continuity chain	Every parent in the chain resolved	no change	High confidence
Patent term adjustment	+755 days, USPTO patent term adjustment record	Nov 20, 2028	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	3 of 3 maintenance fees paid	In force	High confidence
Computed term end	The steps above, in order	Nov 20, 2028	High confidence

This family

US 6,729,248	Term ended Nov 2021	Nov 2021
US 6,773,471	Term ended Jun 2021	Jun 2021
US 7,332,002	Term ended Jun 2021	Jun 2021
US 8,919,266	Term ended Nov 2025	Nov 2025
US 8,124,036	this patent Nov 2028	Nov 2028
US 8,439,989	Term ended Feb 2022	Feb 2022
US 8,293,196	Term ended Oct 2026	Oct 2026
US 9,951,287	Term ended Jan 2022	Jan 2022

8 of 9 applications in this family shown, earliest filings first. 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
Feb 5, 2007 Reel 18852, frame 674	Baldrey, Kenneth E.; Sjostrom, Sharon; French, Nina Bergan; Durham, Michael D.	Ada Environmental Solutions, LLC	Assignment of Assignor's Interest
Dec 19, 2011 Reel 27411, frame 561	Ada Environmental Solutions LLC	Ada-Es, Inc.	Assignment of Assignor's Interest
Oct 23, 2015 Reel 36865, frame 55	Ada-Es, Inc.	Wilmington Trust, National Association, as Collateral Agent	Security Interest
Jul 1, 2016 Reel 39064, frame 268	Wilmington Trust, National Association	Ada-Es, Inc.	Release of Security Interest
Dec 7, 2018 Reel 47742, frame 652	Ada-Es, Inc.	The Bank of New York Mellon, as Administrative Agent	Notice of Grant of Security Interest in Patents
Jun 4, 2021 Reel 56483, frame 657	The Bank of New York Mellon, as Administrative Agent	Ada-Es, Inc.	Termination and Release of Security Interest in Patents
Feb 1, 2023 Reel 62622, frame 51	Ada Carbon Solutions, LLC; Ada-Es, Inc.	CF Global Credit, LP	Patent Security Agreement
Feb 21, 2024 Reel 66643, frame 579	Ada-Es, Inc.	Arq Solutions (Es), Inc.	Change of Name
Dec 27, 2024 Reel 69791, frame 980	CF Global Credit, LP, as Administrative Agent	Arq Solutions, LLC (F/K/A Ada Carbon Solutions, LLC); Arq Solutions (Es), Inc. (F/K/A Ada-Es, Inc.)	Release of Security Interest
Dec 27, 2024 reel/frame not recorded	CF Global Credit, LP, as Administrative Agent	Arq Solutions, LLC (F/K/A Ada Carbon Solutions, LLC)	Release of Security Interest
Dec 27, 2024 reel/frame not recorded	CF Global Credit, LP, as Administrative Agent	Arq Solutions (Es), Inc. (F/K/A Ada-Es, Inc.)	Release of Security Interest
Jan 3, 2025 Reel 69817, frame 645	Arq Solutions, LLC; Arq Solutions (Es), Inc.	Midcap Funding IV Trust	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

Nov 2028

Term ends Nov 20, 2028. No further fees fall due before then

Note

The 755 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 top 25% of utility patents granted in 2012 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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