Patent Yard Sign in
Expired European patentEurope

Methods and apparatus for discrete-frequency tube-wave logging of boreholes

EP 0526554 B1 · Applicant: SCHLUMBERGER LIMITED

EPO PDF

Overview

The published document from the EPO: abstract, claims, description and drawings. Open it full size

Read the whole patent

Listed from its EPO record in Patent Yard's archive of European patents past their term. Its claims, description and drawings are in the EPO PDF and on Google Patents, and the Claude kit works from them.

Google PatentsEPO PDF

Why it's free to use

  • Filed April 8, 1991 and granted March 13, 1996. A European patent lasts at most 20 years from filing, so its term ended April 8, 2011.
  • A supplementary protection certificate, which can extend a medicine or crop-protection patent, adds at most five and a half years, so even that would have ended by October 8, 2016.
  • We check European rights only. A US or other national patent in its family could still be in force: check its family on Espacenet or Google Patents.
FiledApril 8, 1991
PublishedFebruary 10, 1993
GrantedMarch 13, 1996
Term endedApril 8, 2011
Application numberEP 91908764
Classification (CPC)G01V1/005 +1 more

Timeline

Timeline From EPO dates

1992199419961998200020022004200620082010Application filedApril 8, 1991PublishedFeb 10, 1993Patent grantedMarch 13, 1996Term endedApril 8, 2011

Sources & verification

Official EPO records

Full published documentClaims, description and drawings as a PDF.EPOEuropean Patent RegisterProcedure, status, file inspection and legal events.EPOLinked open EP data recordThe bibliographic record this page is built from.EPO

Cross-check elsewhere

Google PatentsFull text, worldwide family, citing patents and legal events.patents.google.comEspacenetNational family members and their legal status.European Patent Office

Everything on this page comes from the EPO record linked above. EPO data used under CC BY 4.0.