Schlumberger's Stephen Harris told Upstream: "Schlumberger was contracted by BP to provide wireline services on the Deepwater Horizon during March and April."
He said the wireline team completed work on the Macondo well on 15 April, but remained the rig and on stand-by from 18 April to 20 April.
It is understood they were prepared to carry out further wireline tests for BP if requested.
