On September 22, 2020, DOJ announced a settlement of $11.5M against Bio-Reference laboratories which "admits to improperly billing government." Part of the billing was for inpatient tests not segregated from outpatient tests during the billing process. Both Medicare and Tricare and discussed. note that since about 2014, Medicare also bundles many outpatient lab tests (but not genetics) under a complex and regularly changing set of rules.
The much larger part of the case relates to payments and values exchanged related to software used in the provider's systems. I don't know the details of the law, but this must be a complex area because of the increasing reliance of the modern health system on electronic transactions, electronic pre-authorization through shared records and software, collating and integrating EHR and lab data, imaging, appropriate use criteria, electronic orders, etc.
I note CMS issued a proposed rule to modernization anti kickback and value sharing regulations, in February 2020 (here). As I understood it (and I'm not an expert here), the rule excluded labs from the modernized value-based or shared savings rules which are required to integrate and cooperate in modern health systems and reduce healthcare fragmentation. In August 2020, CMS announced it was delaying that final rule due to complexities in its structure (here).