Noble Corporation (NE)

[Timothy Smith]

Moody's places 11 offshore drilling companies under review for a downgrade, citing concerns regarding "an extremely challenging operating environment through at least 2017."

The ratings agency expects oil prices to remain volatile and rise minimally through 2017, meaning the energy producers that hire offshore drillers will remain under pressure to keep a lid on spending.

"Sustained weak crude oil prices and a steady supply of newbuild rigs will cause significant credit erosion as contracted backlogs, revenues and cash flows continue to fade," Moody's writes, and "fewer offshore drilling opportunities will be available, resulting in a potentially prolonged period of lower dayrates and fleet utilization."

The companies under review are DO, ESV, NE, RDC, RIG, ATW, SDLP, ORIG, PGN, PACD and Shelf Drilling Midco.

- Timothy Smith