131 patents currently held
Held is read from USPTO's recorded assignments; a transfer never recorded there does not appear.
The next term ends in Apr 2027. from the record
Free plan: 3 watched companies. Pro: unlimited.
Alerts on its grants, lapses and transfers.
26
Ending by 2030
Apr 2027
Next term end
124
Patent families
When these terms end
Held patents by the year their term ends
notable patents
fee due within 90 days
all others
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: the highest-ranked patents in this portfolio by citations and family size. Fee due within 90 days: a maintenance fee is due within 90 days of when this page was computed and not yet paid.
Notable patents
Ranked by citations and family size, against patents of the same kind granted the same year. How we rank
Notable
Ends Oct 2029 · High confidence
Also notable
Ends Oct 2029 · High confidence
Also notable
Ends Aug 2030 · High confidence
DC Bus Voltage Control for Two Stage Solar Converter
US 7,855,906
Cited by 79 later US patents, top 10% of utility patents granted in 2010 in our data, and renewed at 3 of 3 maintenance windows. Protection runs to 2029.
Power Production Control System and Method
US 7,908,036
Cited by 44 later US patents, top 25% of utility patents granted in 2011 in our data, and renewed at 3 of 3 maintenance windows. Protection runs to 2029.
A Controllable Energy Utilization System and Associated Method
US 8,471,406
Cited by 32 later US patents, top 25% of utility patents granted in 2013 in our data, and renewed at 3 of 3 maintenance windows. Protection runs to 2030.
Fee deadlines
Maintenance fees fall due 3.5, 7.5 and 11.5 years after grant. A missed fee ends a patent at the end of the six month grace period that follows, not on the due date.
- 3 fees due Jan 2 to 14, 2027 · next Jan 2
- 1 fee due Mar 15, 2027The maintenance fee for Methods and Systems for Selectively Coupling a Power Conversion System to an Electrical Grid (US 9,136,709) comes due Mar 15, 2027. Unpaid by Sep 15, 2027, it lapses early.
- 2 fees due Apr 24 to 30, 2027 · next Apr 24
- 1 fee due May 3, 2027The maintenance fee for Adaptive Power Conversion System (US 9,178,410) comes due May 3, 2027. Unpaid by Nov 3, 2027, it lapses early.
- 3 fees due Jun 19 to 30, 2027 · next Jun 19
- 3 fees due Jul 7 to 23, 2027 · next Jul 7
- 4 fees due Aug 2 to 27, 2027 · next Aug 2
- 1 fee due Sep 29, 2027The maintenance fee for System and Method for Design and Optimization of Grid Connected Photovoltaic Power Plant with Multiple Photovoltaic Module Technologies (US 9,300,140) comes due Sep 29, 2027. Unpaid by Mar 29, 2028, it lapses early.
- 2 fees due Nov 10 to 12, 2027 · next Nov 10
Recent changes
- 2 of the patents on this record were granted since Aug 16, 2026
- 2 terms have ended since Aug 16, 2026
What they patent
The 5 largest of its 124 families, grouped by real patent family and labeled by the earliest filing in each. No technology classification is inferred from titles.
| Power Production Control System and Method | 3 in force | to Jan 2031 |
| Heat Dissipation System and an Associated Method Thereof | 2 in force | to Feb 2038 |
| Systems and Methods to Control a Power Split Between Energy Generation and Energy Storage Assets | 2 in force | to Jul 2036 |
| Energy Storage System for Renewable Energy Source | 2 in force | to Oct 2035 |
| A Controllable Energy Utilization System and Associated Method | 2 in force | to Aug 2030 |
Patents held now
Soonest term end first.
| Patent | Title | Status | Expires | Confidence |
|---|---|---|---|---|
| US 8,227,683 | System, Method, and Aparatus for Extracting Power from a Photovoltaic Source of Electrical Energy In force · Medium confidence | In force | Medium confidence | |
| US 7,608,937 | Power Generation System and Method for Storing Electrical Energy In force · High confidence | In force | High confidence | |
| US 7,952,232 | Wind Turbine Energy Storage and Frequency Control In force · High confidence | In force | High confidence | |
| US 8,358,033 | Systems, Methods, and Apparatus for Converting DC Power to Ac Power In force · High confidence | In force | High confidence | |
| US 8,427,010 | Dc-To-Ac Power Conversion System and Method In force · High confidence | In force | High confidence | |
| US 8,217,534 | Power Generator Distributed Inverter In force · High confidence | In force | High confidence | |
| US 7,908,036 | Power Production Control System and Method In force · High confidence | In force | High confidence | |
| US 7,990,743 | System and Method for Decreasing Solar Collector System Losses In force · High confidence | In force | High confidence | |
| US 7,855,906 | DC Bus Voltage Control for Two Stage Solar Converter In force · High confidence | In force | High confidence | |
| US 7,890,217 | Integrated Real-Time Power and Solar Farm Control System In force · High confidence | In force | High confidence |
Also on record, not counted in the 131: 6 patents ended · 1 application pending · 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.
Fee due within 90 days marks a patent with a maintenance fee due within 90 days of the date this page was computed and not yet recorded paid, so it can end earlier than the bar shows. A fee left unpaid ends the patent at the close of the six month grace period that follows its due date, not on the due date itself. It is not a prediction that the fee will be missed.
Computed patent terms end on the dates shown. Related patents and pending applications may cover overlapping subject matter.