ATP Drills Successful Well at Matagorda Island

ATP Oil & Gas announced its eleventh successful well in 2004. The Matagorda Island 704 ("MI 704") A-3 well is currently being completed in the Rob M sand. This well, the second to be drilled at ATP's MI 704 block this year, encountered approximately 50' of net natural gas pay in the Rob M sand. The first well at MI 704, the A-1 ST1, was placed on production earlier this year and was completed in the Marg A-3 sand. The proven reserves associated with these reservoirs were not previously included in ATP's reserve report but are expected to be added to the report at the end of 2004. ATP is the operator of the MI 704 block.

T. Paul Bulmahn, Chairman and President of ATP, stated, "Based on the positive results of the first two wells at MI 704 during 2004 we are considering possible expansion of development at this field in 2005. With available infrastructure in the Gulf of Mexico, ATP is able to quickly bring on production these and other projects. The remainder of 2004 is already scheduled to be a very active development period for ATP."