Investors in the rig market shouldn't be shocked at all that Seadrill (NYSE:SDRL) has been able to capture market share from its competitors in the floating-rig market during this recent downturn. What some may have not noticed, though, is that it is doing the same in the jackup market as well. The company recently signed $300 million in contracts for its jackup fleet for over two years of service, while both Hercules Offshore (NASDAQ: HERO) and Rowan (NYSE: RDC) have not seen as great of success recently.

Should this make investors in Hercules and Rowan nervous? While both still have a considerable amount of their fleet under contract, there is one thing that should make investors in one of these companies very nervous. Tune into the video below to find out what it is.