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, 3 name Mitsui Chemicals Inc. as their current owner. Each row says so.
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. 2015 to 2033.
US 9,052,436
Method for Manufacturing Resin for Urethane-Based Optical Material, Resin Composition for Same, and Optical Material Manufactured Thereby
Dec 29, 2031
US 9,372,281
Method for Preparing Thioepoxy-Based Optical Material and Polymerizable Composition Thereof
Jan 21, 2033
US 9,658,364
Method for Storing Episulfide Compound and Method for Preparing Thioepoxy-Based Optical Material Using Said Episulfide Compound
Jan 21, 2033
20192023202720312033
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 Dec 2031 · High confidence
Granted 2015 and renewed at every maintenance window due so far. Protection runs to 2031.
now held by Mitsui Chemicals, Inc.
Also notable
Ends Jan 2033 · High confidence
Granted 2016 and renewed at every maintenance window due so far. Protection runs to 2033.
now held by Mitsui Chemicals, Inc.
Also notable
Ends Jan 2033 · High confidence
Granted 2017 and renewed at every maintenance window due so far. Protection runs to 2033. A terminal disclaimer caps this term to an earlier patent's.
now held by Mitsui Chemicals, Inc.
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. 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.