OneSubsea™, a Cameron and Schlumberger company, Helix Energy Solutions Group, Inc. and Schlumberger today announced that they have entered into a letter of intent to form an alliance to develop technologies and deliver services to optimize the cost and efficiency of subsea well intervention systems. Helix is a leading subsea well intervention provider, with the largest fleet size of well intervention vessels, and an unequalled track record in cost-effective subsea well intervention. OneSubsea, a preeminent solution provider for subsea well control, with a global footprint of executed major projects, has significant experience in the manufacture and supply of subsea well intervention equipment and services.