There is a definition of "qualified divesture" in the legislation itself, and no, it is not soley up to the President's determination as defined in the statute itself, because it clearly qualifies the president's determination, and stipulates what it must determine as a matter of fact:You can challenge anything, but the law is written in plain language. Given there is no definition of "qualified divestiture," and the fact that it's up the President's determination, there's no real challenge in court.
Blame the original law for being so ambiguous.
What competitor is going to challenge this? The ones who donated $1M to his inauguration fund? They know Trump can do anything to make their lives very difficult. So who's going to poke the bear?
<<NOTE: President. Determinations.>> The term ``qualified
divestiture'' means a divestiture or similar transaction that--
(A) the President determines, through an interagency
process, would result in the relevant foreign adversary
controlled application no longer being controlled by a
foreign adversary; and
(B) the President determines, through an interagency
process, precludes the establishment or maintenance of
any operational relationship between the United States
operations of the relevant foreign adversary controlled
application and any formerly affiliated entities that
are controlled by a foreign adversary, including any
cooperation with respect to the operation of a content
recommendation algorithm or an agreement with respect to
data sharing.
The statute itself even gives explicit parameters for judicial review -- although it is possible even that could be challenged, but just the fact it gives parameters for judicial review of, among another things, any "determination" made -- which would include the Presidents' determinations "through an interagency process":
SEC. 3. <<NOTE: 15 USC 9901 note.>> JUDICIAL REVIEW.
(a) Right of Action.--A petition for review challenging this
division or any action, finding, or determination under this division
[[Page 138 STAT. 960]]
may be filed only in the United States Court of Appeals for the District
of Columbia Circuit.
(b) Exclusive Jurisdiction.--The United States Court of Appeals for
the District of Columbia Circuit shall have exclusive jurisdiction over
any challenge to this division or any action, finding, or determination
under this division.
(c) Statute of Limitations.-- <<NOTE: Deadlines.>> A challenge may
only be brought--
(1) in the case of a challenge to this division, not later
than 165 days after the date of the enactment of this division;
and
(2) in the case of a challenge to any action, finding, or
determination under this division, not later than 90 days after
the date of such action, finding, or determination.