The present invention is directed to a method and apparatus for bulk erasure of disk drives. According to the novel invention, one or more relatively small-sized permanent magnets or electromagnets are configured to be brought into close proximity to a particular disk surface of the disk drive and to produce a concentrated magnetic force that erases the disk. Notably, the magnets are sized and configured to create a focused magnetic field, and correspondingly to prevent stray magnetic fields, which could otherwise be harmful to magnetically sensitive components of the disk drive, such as motor magnets. The magnets may be configured to gain access to the disk surface through one or more openings on a covered disk drive, e.g., through an actuator and/or servo track writer opening. The magnets and resultant focused magnetic field may be large enough to offer substantially full radial coverage of the disk, or may be smaller and configured to move (e.g., “sweep”) across the surface of the disk for full coverage accordingly.