A paleomagnetic study of sediments from Deep-Sea Drilling Project (DSDP) sites 290, 292, and 294 suggests that the West Philippine Basin originated between 5¿ and 10¿S. Results for site 292 are particularly consistent; a group of 20 closely spaced samples at the sediment-basalt interface has a mean absolute paleolatitude and 95% confidence interval of 4.9¿¿2.0¿. An equatorial crossing is implied by the trend of paleoinclinations as a function of age for 73 additional samples from site 292 and concurrent results from sites 290 and 294. Origin of the West Philippine Basin in southern latitudes is also consistent with the phase shifting of marine magnetic anomalies, which must be inverted to be matched with a set of worldwide Eocene reversals. Two well-defined paleomagnetic pole positions are determined if the low amplitude of these east-west anomalies, in comparison to similarly oriented anomalies in the Pacific and Indian oceans, is due to a rotation of this plate. One of these is consistent with paleopoles calculated from the 'absolute' motion of the Pacific and directions of relative motion between the Philippine and the Pacific plate. This suggests a clockwise rotation of 60¿ between the Philippine plate and the magnetic pole and is similar to results from the study of Miocene rocks on Guam. This may imply that both Guam and the West Philippine Basin have undergone the same past plate motion and that the rotation of Guam is not due to a simple bending of the Marianas arc.