Some already got leaked in a big way:
https://www.foxsports.com/mlb/story/financial-records-show-pirates-win-while-losing-20613304-082310
One antitrust ruling argued that the exemption should only apply to player contracts.
https://www.chicagotribune.com/news/ct-xpm-1993-08-06-9308060306-story.html
Obviously, MLB wants to stay out of lawsuits and legislative scrutiny as much as possible that could lead to such interpretations and rulings. This makes the move to clear cut parts of the minors a headscratcher, as it put the sport on Congress' radar.
It's evident that that was one of the reasons it took so long for the Expos to leave, both from the Expos side (whose Québécois owners filed a RICO suit against MLB) and the Angelos factor (even though Selig appeared to have best interests of baseball clauses applicable in the situation, especially since Baltimore's only codified rights were confined to the counties that touched Baltimore city and county).
This figures to be relevant to the noises from Montreal about getting another team (outside of financial realities related to business and the fanbase supporting a team at MLB-caliber revenue levels). Stephen Bronfman has emerged as face of potential ownership, which seems problematic given his refusal along with the other Québécois owners to get a ballpark and new ownership deal done when the team was actually there, or to even meet Loria's cash calls to maintain ownership position. Oh yeah, and he just happened to be a plaintiff in the RICO suit against the organization he would want to rejoin.
The antitrust exemption that applies to baseball is fairly straight-forward. It's from a Supreme Court ruling in a case called
Federal Baseball from 1922. The holding is indeed that baseball is not interstate commerce (and therefore exempt from federal antitrust laws), because "the business is giving exhibitions of base ball, which are purely state affairs." The case was upheld by the Supreme Court in 1953 and then again in 1978. As it's a Supreme Court case, the only way it gets overturned is by the Supreme Court itself or by Congress.
There are a few interesting bits about the stance of this case, one being that at least one current justice (Gorsuch) has strongly suggested he'd overrule it. If a huge business entity can't rely on Gorsuch's vote in keeping it immune from a suit, it is - and let me summon my decade of practicing antitrust law for this highly technical term - freaked.
Another is that it's not clear what happens if the antitrust exemption is stripped off; presumably you'd end up with the same level of antitrust regulation as in the other sports, which have much more limited immunity, but largely tied to their collective bargaining agreements with players (which therefore provide no immunity from suits by non-union MiLB players). A final one is that, at least as a technical matter, the antitrust exemption in Federal Baseball is only a federal one - it was only the 1978 Curt Flood case that also exempted baseball from state antitrust laws. So you'd need to overrule more than one case to get rid of it.
Basically, the Supreme Court has repeatedly bent over backwards to exempt MLB from antitrust laws. It's not clear that it would do so again if needed.