Abstract-As remote health monitoring BASN technology matures and begins to proliferate, several issues related to the secure sharing of the resulting medical electronic data have come to the fore. This includes the need to provide the data owner (BASN user / patient) and the data consumers (healthcare providers, insurance companies, medical research facilities) secure control over the medical data as it is shared between these various stakeholders. In this paper, we focus on three secure sharing use-cases: proof of ownership, wherein the data owner must prove that she/he is the originator of the data; data tracking, wherein the data owner must trace unauthorized sharing of her/his biosignal data; and content authentication, wherein the data owner must prove whether the biosignal data has been maliciously altered. To address these usecases, we develop a robust watermarking technique to embed security information into biosignal data such that the semantic fidelity of the data is unaffected, the bio-signal waveforms are altered imperceptibly, and the watermark is not easily corrupted, recovered or spoofed by malicious data consumers. Based on experimentally collected datasets from a gait-stability monitoring BASN, we show that our watermarking technique can robustly and effectively embed up to 1000 bit watermarks under these constraints.