Patent application 14464233 (US), filed 2014-08-20
Publication number: US20150053413A1
Title: METHOD OF PROVIDING BUOYANCY
CPC codes: F16L   1/24
B63B  22/00
B63G   8/001
B63G2008/005
E21B  17/012
Office action: rejection, dated 2015-10-15
Rejection reasons: obviousness_103
indefiniteness_112
Prior art cited: ref_id: EP 1867564
ref_type: patent
severity: obviousness
ref_id: 20110111991
ref_type: patent
severity: obviousness
Final disposition: rejected (2015-10-15)