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Systems and Methods of RF Power Transmission, Modulation, and Amplification, Including Waveform Distortion Compensation Embodiments

US 7,945,224 Lapsed on the fee record
OverviewFamilyAssignmentsSources & methods
Collateral for a security interest recorded Jan 4, 2019 (Mintz Levin Cohn Ferris Glovsky and Popeo, P.C.).

Lapsed May 17, 2023 on the fee record · Medium confidence

Why Medium: A terminal disclaimer is on file (approved) with no resolved reference, so the term may end earlier.

Third maintenance fee unpaid; grace period ended.

Filed Aug 24, 2006 as application 11/509,005 · Granted May 17, 2011
Base term, 20 years from filing, plus 7 days of patent term adjustment (USPTO delay)
Today
Lapsed May 17, 2023
2005 2026
Clock starts
Oct 24, 2005
No longer in force
May 17, 2023
Granted
May 17, 2011
Term would have run to
Oct 31, 2025
base term 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
7
Days of term adjustment
Read from the USPTO patent term adjustment record, 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 grant. This counts the ones the record shows paid.
19
Family applications on record here
Applications sharing this one's continuity chain whose file history this site holds. The family may have others.

Its term would have run to Oct 31, 2025: its 20-year base term plus 7 days of term adjustment for prosecution delay. A terminal disclaimer is on file with no resolved reference, so no cap is applied and none is guessed. Confidence: Medium. 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.
StepInputDate after this stepConfidence
Base term, 20 years from filingClock starts Oct 24, 2005, when application 11/256,172, the earliest non-provisional in its chain, was filed (this one was filed Aug 24, 2006)Oct 24, 2025High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+7 days, USPTO patent term adjustment recordOct 31, 2025High confidence
Terminal disclaimer capDisclaimer on file (approved), reference document not resolvedno cap applied, and none guessedMedium confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events2 of 3 maintenance fees paidlapsed May 17, 2023High confidence
Computed term endThe steps above, in orderMay 17, 2023Medium confidence

This family

US 7,184,723Lapsed on the fee record
Feb 2019
Feb 2019
US 7,835,709Lapsed on the fee record
Nov 2022
Nov 2022
US 7,945,224this patent
May 2023
May 2023
US 7,355,470Lapsed on the fee record
Apr 2020
Apr 2020
US 8,428,527Term ended
Oct 2025
Oct 2025
US 8,406,711In force
no later than Nov 2026
no later than Nov 2026
US 7,526,261Term ended
Apr 2026
Apr 2026
US 8,351,870In force
no later than Apr 2027
no later than Apr 2027
8 of 19 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.
RecordedAssignorAssigneeConveyance
Oct 19, 2006
Reel 18410, frame 655
Sorrells, David F.; Rawlins, Gregory S.; Rawlins, Michael W.Parkervision, Inc.Assignment of Assignor's Interest
Jan 4, 2019
Reel 47905, frame 316
Parkervision Inc.Mintz Levin Cohn Ferris Glovsky and Popeo, P.C.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.

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