The Deepwater Horizon oil spill happened well over a year ago now. For the most part, the oil has been cleaned up, businesses and resorts are back to relative normality, and people have moved past the disaster.

But there are a few items of business still outstanding for those involved in the spill -- mainly the fact that BP (NYSE: BP), which has taken a majority of blame for the spill, wasn't the only owner of the oil rig and wasn't the only company responsible for its operation. Japan's Mitsui settled for $1.1 billion to cover the company's 10% stake in the Macondo project, and earlier this week Anadarko Petroleum (NYSE: APC), a 25% owner, settled for $4 billion.

That leaves us with Halliburton (NYSE: HAL) and Transocean (NYSE: RIG) as the two main players with outstanding uncertainty. Both were subcontractors on the project, and both say they're not responsible for the oil spill or any of its liabilities. But the settlements by other players and a recent report seem to be working against them.

A report from the Bureau of Ocean Energy Management spread the blame out among almost everyone involved in the disaster. BP, Halliburton, and Transocean were all named on incident of noncompliance charges.

A settlement on the horizon
One of the benefits for Anadarko, and others, settling with BP is the reduction in potential risk going forward. Lawsuits are not only expensive if you lose; they're expensive to fight as well. With everyone around them settling, there will be mounting pressure on Halliburton and Transocean to do the same.

But a settlement also has implications for others involved in offshore drilling. The oil spill and regulatory changes have affected potential liabilities during downtime for rig owners such as SeaDrill (NYSE: SDRL), Transocean, and Dryships' (Nasdaq: DRYS) subsidiary Ocean Rig (Nasdaq: ORIG).

A settlement in the near future might help make that picture a little clearer, at a cost to Halliburton and Transocean.

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