Keystone Tower Systems, Inc.

33 patents currently held · Updated Nov 14, 2026

Held is read from USPTO's recorded assignments; a transfer never recorded there does not appear.

Ending by 2030

Jan 2030

Next term end

When these terms end

5 yrs10 yrs20 yrs

Held patents by the year their term ends

20262027202820292030203120322033203420352036203720382039204020412042204320442045

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.

1 fee due Dec 27, 2026
The maintenance fee for Wind Turbine Tower Attachment (US 11,686,155) comes due Dec 27, 2026. Unpaid by Jun 28, 2027, it lapses early.
1 fee due Feb 22, 2027
The maintenance fee for Spiral Forming (US 11,731,181) comes due Feb 22, 2027. Unpaid by Aug 23, 2027, it lapses early.
1 fee due May 26, 2027
The maintenance fee for Sheet Transitioning in Spiral Formed Structures (US 10,486,212) comes due May 26, 2027. Unpaid by Nov 26, 2027, it lapses early.
2 fees due Jun 3 to 5, 2027 · next Jun 3
1 fee due Jul 30, 2027
The maintenance fee for Flange Fitting for Tubular Structures (US 11,883,907) comes due Jul 30, 2027. Unpaid by Jan 31, 2028, it lapses early.
2 fees due Oct 5 to 21, 2027 · next Oct 5

Which patents, and when each one lapses · Pro

Recent changes

Nothing was recorded against this company's patents in the last 90 days.

Patents held now

Soonest term end first. Each date below is computed on that patent's own page, which shows the rule, the adjustments and the fee history it was derived from.

Patent	Title	Status	Expires	Confidence
US 10,060,149	Tapered spiral welded structure In force Term ends Jan 25, 2030 · From the USPTO record	In force	Term ends Jan 25, 2030	From the USPTO record
US 11,834,856	Tapered spiral welded structure In force Term ends Jun 7, 2030 · From the USPTO record	In force	Term ends Jun 7, 2030	From the USPTO record
US 9,475,153	Tapered spiral welded structure In force Term ends Jun 28, 2030 · From the USPTO record	In force	Term ends Jun 28, 2030	From the USPTO record
US 10,895,088	Tapered spiral welded structure In force Term ends Dec 21, 2030 · From the USPTO record	In force	Term ends Dec 21, 2030	From the USPTO record
US 8,720,153	Tapered spiral welded structure In force Term ends Sep 17, 2031 · From the USPTO record	In force	Term ends Sep 17, 2031	From the USPTO record
US 10,195,653	Tapered Structure Construction In force Term ends Sep 20, 2032 · High confidence	In force	Term ends Sep 20, 2032	High confidence
US 10,974,298	Tapered Structure Construction In force Term ends Sep 20, 2032 · High confidence	In force	Term ends Sep 20, 2032	High confidence
US 11,571,727	Tapered structure construction In force Ends no later than Sep 20, 2032 · From the USPTO record	In force	Ends no later than Sep 20, 2032	From the USPTO record
US 12,226,813	Tapered structure construction In force Term ends Sep 20, 2032 · From the USPTO record	In force	Term ends Sep 20, 2032	From the USPTO record
US 9,302,303	Tapered Structure Construction In force Term ends Feb 13, 2033 · High confidence	In force	Term ends Feb 13, 2033	High confidence

10 of 33 patents shown.

Pro members see all 33.

Pro members: see all 33 patents

Sources and methods

Compiled from the USPTO record, grants, published applications and recorded assignments, not yet reviewed by hand. How this record was built

Computed patent terms end on the dates shown. Related patents and pending applications may cover overlapping subject matter.

Export every term end as CSV · Pro

Published applications

Every application published under this name has become a patent.