There is no universally accepted definition of big data, yet it is characterized by widely recognized attributes. Medical big data embodies all these characteristics. These attributes present certain challenges for big data and its applications. We elaborates on medical big data and its interpretation, encompassing three representative of medical big data that exhibit distinct compositional features. We discuss misconceptions in medical big data applications emphasizing that the implementation of big data requires technical analysis, and address unique technological, legal, and ethical challenges. Here we focus on core issues and controversies in medical big data, particularly the challenges of confirming property rights and potnetial solutions, with special attention paid to Aggregated Data rights. We also analyze the applicability of traditional intellectual property frameworks and point out the impact of technological advancements on right confirmation.