A preliminary study on seizure detection and forecasting with a minimally invasive sub-scalp ultra-long term EEG monitoring device revealed successful and accurate monitoring of seziures comparable with conventional EEG monitoring. Five patients with refractory epilepsy were implanted with sub-scalp devices providing two channels of continuous data from both hemispheres of the brain, captured using a behind-the-ear system. This system also powered the device and allowed a wireless transfer to mobile phone. The sub-scalp EEG recordings were compared to conventional EEG readings during a 1-week ambulatory video-EEG monitoring session. Sub-scalp EEG monitoring and devices were well-tolerated with no major complications. It also led to successful seizure forecasting comparable to that achieved with intracranial EEG. All participants had an evident sleep-related transients in the sub-scalp recordings.