The chief financial officer of oil giant BP has topped up his stake in the group with a £233,318 share purchase following last week's court ruling. Brian Gilvary, who was appointed to his role at the start of 2012, acquired 50,000 shares at 466.64p apiece.Last week the group was slapped with one of the largest class action lawsuits seen in US history relating to the 2010 Gulf of Mexico oil spill.In response, the group issued a statement saying it "strongly disagrees" with the decision and pledged to appeal to the US Court of Appeals."BP believes that the finding that it was grossly negligent with respect to the accident and that its activities at the Macondo well amounted to willful misconduct is not supported by the evidence at trial," its statement read."The law is clear that proving gross negligence is a very high bar that was not met in this case. BP believes that an impartial view of the record does not support the erroneous conclusion reached by the District Court." Top Director BuysBP (BP.) Director name: Mr Brian GilvaryAmount purchased: 50,000 @ 466.64p Value: £233,320Xaar (XAR) Director name: Mr Ramon BorrellAmount purchased: 25,000 @ 420.17p Value: £105,042Menzies(John) (MNZS) Director name: Mr Iain NapierAmount purchased: 2,000 @ 598.02p Value: £11,960Top Director SellsE2V Technologies (E2V) Director name: Mr Charles HindsonAmount sold: 151,886 @ 155.00p Value: £235,423