Shareholders of offshore drilling contractors Ensco and Pride International will vote on May 31 on the proposed acquisition of Pride by Ensco for more than $7 billion.

The deal, struck in early February, is set to create the world's second-largest rig fleet, and the combined company would challenge Seadrill for the number-two ranking by market capitalization.

The two companies also disclosed new names for 23 of Pride's 26 rigs. The three shallow-water rigs not renamed - Pride Pennsylvania, Pride Hawaii and Pride Wisconsin - are not currently being marketed and were all built in the 1970s.

Ensco Chief Executive Dan Rabun, noting that Ensco had sold four of its own shallow-water jackup rigs last year, said last week there would be opportunities to dispose of some non-core assets after the acquisition, but gave no further details.

Rivals including Transocean and Noble Corp are taking hard looks at their fleets in order to improve their overall quality and age profile.
An Ensco spokesman was not immediately available for comment on Tuesday.