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PCE
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DIFF Subgroup
E21D 15/30

by means expanded or contracted by pressure applied through the medium of a fluid or quasi- fluid, e.g. rubber

Introduced: September 1968

Title

Titles differ between systems:

IPC: by means expanded or contracted by pressure applied through the medium of a fluid or quasi-fluid, e.g. rubber

CPC: by means expanded or contracted by pressure applied through the medium of a fluid or quasi- fluid, e.g. rubber

Full Title

Full titles differ between systems:

IPC:

Props; Chocks > Telescopic props > with parts held relatively to each other by friction or gripping, e.g. using wedges > by means expanded or contracted by pressure applied through the medium of a fluid or quasi-fluid, e.g. rubber

CPC:

Props (in the building art E04G25/00); Chocks > Telescopic props (general means for fixing telescopic parts together ) > with parts held relatively to each other by friction or gripping > by means expanded or contracted by pressure applied through the medium of a fluid or quasi- fluid, e.g. rubber

Of 2 combined children, 0 exist in both systems.

2 codes are CPC-only extensions.

Child Classifications

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Top Applicants

Top Applicants (IPC)

Class E21,2013–2023, worldwide · Source: EPO PATSTAT

  1. HALLIBURTON ENERGY SERVICES GROUP US 26,607
  2. PETROCHINA COMPANY 14,382
  3. SINOPEC (CHINA PETROCHEMICAL CORPORATION) 10,137
  4. CNPC (CHINA NATIONAL PETROLEUM CORPORATION) 6,517
  5. BAKER HUGHES US 6,269
  6. SCHLUMBERGER TECHNOLOGY US 5,929
  7. SAUDI ARABIAN OIL COMPANY SA 5,880
  8. SOUTHWEST PETROLEUM UNIVERSITY 4,477
  9. CHINA UNIVERSITY OF MINING AND TECHNOLOGY 4,357
  10. SCHLUMBERGER TECHNOLOGY NL 4,219

Top Applicants (CPC)

Class E21,2013–2023, worldwide · Source: EPO PATSTAT

  1. HALLIBURTON ENERGY SERVICES GROUP US 27,652
  2. SAUDI ARABIAN OIL COMPANY SA 7,755
  3. PETROCHINA COMPANY 7,025
  4. BAKER HUGHES US 6,589
  5. SCHLUMBERGER TECHNOLOGY US 6,151
  6. SINOPEC (CHINA PETROCHEMICAL CORPORATION) 4,443
  7. SCHLUMBERGER TECHNOLOGY NL 4,255
  8. CNPC (CHINA NATIONAL PETROLEUM CORPORATION) 3,991
  9. SERVICES PETROLIERS SCHLUMBERGER FR 3,300
  10. SCHLUMBERGER CANADA CA 3,086