What is the difference between Data Assertion List and Data Accesstion List?
Data Rights is a complex issue and you should get the help and advice of your legal counsel as you are doing. The lists you referenced are not specifically defined in the FAR, but FAR Section 27.4 - Rights in Data and Copyrights and DFARS 227.71 Rights in Technical Data and DFARS 227.72 Rights in Computer Software and Computer Software Documentation are references for Data Rights.
The site below is a reference regarding a Data Accession List from a previous AAP response that may further assist you:
Open full Question Details