Media Matters made a good argument that Fox made an illegal contribution to the Trump campaign when it shared confidential Biden-campaign information with Jared Kushner and that the Trump campaign illegally accepted it.
From the complaint, which also names Trump's Make America Great Again PAC and its treasurer as respondents (citations excluded):
[Election law] prohibits any candidate, candidate’s political committee, or any person from knowingly accepting or receiving a contribution from a corporation. Similarly, a corporation is prohibited from making a contribution. A contribution includes any direct or indirect “gift of money, or any services, or anything of value,” including an in-kind service provided without compensation, “made by any person for the purpose of influencing any election for Federal office.” The Commission has treated material non-public information such as information about advertising, messaging, and other campaign strategy as a thing of value.
Here, it appears that Murdoch and Fox Corporation provided the Committee with material non-public information about the Committee’s opponent’s advertisements. Specifically, Murdoch allegedly conveyed the actual advertisements that the Biden campaign paid Fox Corporation to air on its television outlets to the Committee before the advertisements aired. The Biden advertisements were material non-public information and, therefore, were of value to the Committee. As such, Fox Corporation, through Murdoch, appears to have made an impermissible corporate contribution to the Committee and the Committee also violated the Act by accepting the corporate contribution.
I wrote about this further for Crooks and Liars yesterday. You can read more of my discussion here.