The biggest catalyst for BP shares in terms of removing the gross negligence argument once and for all could come in late July when the Marine Board of Investigation releases its report. From a legal standpoint it is more important than the presidential commission, Oppenheimer's Gheit said, and will serve as a the basis for the Justice Department, state and local governments. The panel reviewed the blowout preventer specifically and has made it clear that it was not a maintenance problem or an operating problem, but an equipment failure caused by design. On the one-year anniversary of the oil spill, BP filed lawsuits against Cameron International, the maker of the blowout preventer, along with rig operator Transocean and deepwater engineer Halliburton. BP sued Transocean for $40 billion -- BP has so far written off $41 billion in oil spill charges -- citing failures in every single aspect of Transocean's Deepwater Horizon rig systems and devices. BP is suing Cameron International for faulty design in the blowout preventer, which echoes the comments from the government report on the device. BP had previously stated in its interim oil spill report that Halliburton's "bad cement job" was to blame, and now is suing Halliburton for fraud, negligence and concealing material facts in connection with its work on the rig. One important legal fact in the BP suits filed on the one-year anniversary of the oil spill is that BP's right to sue would have expired had it not filed within a year of the disaster. The Oppenheimer analyst noted that of the $41 billion written off by BP for the oil spill, the total amount it has paid, now above $20 billion, will likely keep increasing by another billion or two to account for cleanup costs which are running at $5 million per day, though down from $20 million a day in January. The biggest liability that BP faces is the penalty under the Clean Water Act, which at a low end will be roughly $4.5 billion, and, in the case of gross negligence, as high as $17 billion to $21 billion. Yet BP can't not be found gross negligent and its Macondo well partners Anadarko (25%) and Mitsui (10%) not be forced to pay some portion of the liabilities. "It's not if the partners pay; it's how much and when," Gheit said. Argus Research's Weiss has assumed from day one of the oil spill that at some point, Anadarko will have to take a charge for some portion of the liabilities. The Oppenheimer analyst is betting that BP will ultimately have a significantly lower liability than the $41 billion it has already written off. "The jury is still out, but so far most of the report has more or less helped BP's case, at least for not being grossly negligent," Gheit concluded. "The July report will be the basis for all litigation, and we will know better, not exactly to the last million, but will it be $5 billion or $20 billion more, and that's very important point for BP and an inflection point for BP shares," the Oppenheimer analyst predicted. Indeed, a catalyst is just what the range-bound BP shares need to finally pass the year-long slick on which they've skidded. -- Written by Eric Rosenbaum from New York.