0 patents currently held, every record listed here
3 more in force are now held by other companies
Held is read from USPTO's recorded assignments; a transfer never recorded there does not appear.
This portfolio holds none of the 3 US patents in force on its record. from the record
Of the 3 now held by other companies, 2 name Weatherford Canada Ltd. as their current owner, and 1 more name another party. Each row says which.
Free plan: 3 watched companies. Pro: unlimited.
Alerts on its grants, lapses and transfers.
0
Ending by 2030
none
Next term end
When these terms end
Each bar runs from grant to computed term end. 2014 to 2033.
US 10,400,579
Optical Device for Measuring a Physical Parameter in a Hydrogen Contaminated Sensing Zone
Apr 1, 2029
20182022202620302033
Every computed term in this portfolio is shown above.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
Notable patents
Ranked by citations and family size, against patents of the same kind granted the same year. How we rank
None of the currently held patents qualifies as notable.
Formerly held, still cited
Notable
Ends Apr 2029 · High confidence
The most cited patent in this portfolio, cited by 22 later US patents, top 25% of utility patents granted in 2019 in our data. Protection runs to 2029.
now held by Weatherford Canada Ltd.
Also notable
Ends Nov 2033 · High confidence
Granted 2016 and renewed at every maintenance window due so far. Protection runs to 2033.
merged into Weatherford Engineered Chemistry Canada Ltd. - now held by Weatherford Canada Ltd.
Also notable
Ends Oct 2028 · Medium confidence
Renewed at every maintenance window since the 2014 grant; no more fees are due before its term ends in 2028.
now held by Weatherford Canada Ltd.
Fee deadlines
No maintenance fee falls due on this company's record before Nov 10, 2027.
Recent changes
Nothing was recorded against this company's patents in the last 90 days.
Patents held now
Soonest term end first.
Also on record: 3 patents in force now held by others · 13 patents ended · 2 applications abandoned. List them
Sources and methods
Compiled from USPTO application file histories, grants and recorded assignments, with the company's own names reviewed by hand. How this record was built
Portfolio grouped automatically from ownership conveyances to the names matched to this company, usually every name that begins with its own, so it counts patents an affiliate holds; each list row names the holder of record. Security interests are excluded and ambiguous records are not reviewed by hand.
Computed patent terms end on the dates shown. Related patents and pending applications may cover overlapping subject matter.
2 computed term dates come from a chain with an unresolved parent. A continuity parent has not yet been fetched from USPTO's records. The term is dated from this application's own claim; no earlier date is assumed until the parent is resolved.