We present a 3D multi-shank linear electrode array for semichronic laminar neural recording in drug-resistant epilepsy patients. The 3D array comprises nine parallel shanks (3x3, lateral spacing: 1 mm) fixed on a 4.5x4.5 mm PEEK platform. An individual shank (185 μm OD) has a conical-shaped taper and contains 16 or 24 recording sites (15 μm OD microwires, Pt/Ir–90/10%; inter-site distances may vary between 50–200 μm). The microwires provide an uninterrupted connection between the recording sites and a PCB with Omnetics connectors for headstage input. The 3D array allows for easy and quick operation during surgical implantation. We successfully implanted (up to 10 days) several prototypes of the 3D array in combination with intracranial EEG electrodes in five patients. After surgical removal of the arrays, we performed in vitro targeted patch clamp experiments near electrode tracks with anatomical recovery of patched cells and only a slight (17±8%) drop in the number of connected pairs relative to slices made from tissue without electrode tracks. The application of a 3D array confirmed the strong power for low- and middle-frequency bands in supragranular layers compared to infragranular layers and the existence of powerful human pyramidal cell to interneuron spike to spike coupling and relatively weaker pyramid-to-pyramid interactions in vivo. We conclude that the 3D electrode array is well-applicable for the laminar recording of LFP signal specificity and is successful in identifying Hebbian sequences of firing in groups of relatively closely spaced pyramidal cells and interneurons in the human cortex.