Patent assignee · GB · COMPANY

Plexus Ocean Systems Ltd.

12Patents
2Active
12Granted
34Portfolio score

Filing activity: Jun 22, 1987 → Sep 24, 2007 · 2 expiring within 5 years

Most-cited patents

PatentTitleAreaCited byStatus
US4856592A Annulus cementing and washout systems for wells Fixed Constructions 99 Expired
US6571877B1 Wellhead Fixed Constructions 44 Expired
US4938289A Surface wellhead Fixed Constructions 34 Expired
US4794988A Surface wellhead Fixed Constructions 26 Expired
US7128143B2 Externally activated seal system for wellhead Fixed Constructions 24 Expired
US7111688B2 Clamping well casings Mechanical Engineering; Lighting; Heating 22 Expired
US6092596A Clamping well casings Fixed Constructions 21 Expired
US7740061B2 Externally activated seal system for wellhead Fixed Constructions 19 Active
US7344162B2 Pipe joint Emerging Cross-Sectional Technologies 14 Expired
US7648176B2 Pipe joint Emerging Cross-Sectional Technologies 11 Active
US6095243A Washout arrangement for a well Fixed Constructions 7 Expired
US7104318B2 Self-contained centralizer system Fixed Constructions 7 Expired

Source: USPTO / EPO open patent data. Counts and citation impact are objective bibliographic measures.