Method and system for measuring the relief of an object

US RE42,899 Lapsed on the fee record

Overview Sources & methods

Lapsed Apr 4, 2018 on the fee record · From the USPTO record

Computed 20-year base term

Third maintenance fee unpaid; grace period ended.

Named at grant Zygo Corporation · find this owner

Filed Jul 14, 2000 as application 11/581,230 · Granted Nov 8, 2011

Base term, 20 years from filing, plus 434 days of patent term adjustment (USPTO delay)

Today

Lapsed Apr 4, 2018

2000 2026

Clock starts
Jul 14, 2000

No longer in force
Apr 4, 2018

Granted
Nov 8, 2011

Term would have run to
Sep 21, 2021

base term patent term adjustment after the term ends fee events Updated Nov 15, 2026 · includes USPTO assignment & status data published Nov 15, 2026 and grant & fee data published Nov 10, 2026 (weekly) · how we know

434

Days of term adjustment

Read from the original patent's USPTO patent term adjustment record, which governs a reissue. Not recalculated here.

Unresolved

Terminal disclaimer

On file, reference document not resolved, so the date above is an upper bound. We do not guess the cap.

2 of 3

Maintenance fees paid

Three maintenance fees fall due, at 3.5, 7.5 and 11.5 years from the original patent's grant, which is not on record here. This counts the ones the record shows paid.

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 Jul 14, 2000, when this application, 11/581,230, was filed	Jul 14, 2020	High confidence
Continuity chain	A reissue: its term follows the original patent's, with the original's term adjustment	follows the original patent	Medium confidence
Patent term adjustment	+434 days, the original patent's USPTO patent term adjustment record, which governs a reissue (35 U.S.C. 251). This reissue's own record carries none	Sep 21, 2021	Medium confidence
Terminal disclaimer cap	Disclaimer on file (approved), reference document not resolved	no cap applied, and none guessed	Medium confidence
Patent term extension	None on file	no change	High confidence
Fee events	2 of 3 maintenance fees paid	lapsed Apr 4, 2018	High confidence
Computed term end	The steps above, in order	Apr 4, 2018	From the USPTO record

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.

Not on this page: the patent's family, its recorded assignments and its citation count. USPTO's assignment records, linked above, list every recorded assignment.

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.

Method and system for measuring the relief of an object

Lapsed Apr 4, 2018 on the fee record · From the USPTO record

20-year base term ended Jul 14, 2020

How we calculated this date

Sources