The story published at the Huffington Post alleged that Eric Bolling had sent extremely lewd texts including pictures of male genitalia to at least three female colleagues of his at Fox News Business and Fox News.
According to the lawsuit filed in ny state court on Wednesday, Bolling is seeking damages and injunctive relief from what he believes to be Ali's efforts at slander through "intentional and/or highly reckless publication of actionable false and misleading statements" about his behavior and demeanor.
The summons accuses Ali of "reckless publication of actionable false and misleading statements about the plaintiff's conduct and character".
The female employees said they knew it came from Bolling because of the phone number used in the message, with The Huffington Post citing more that dozen sources in their report.
The suit was filed by Michael Bowe, an attorney at the law firm Kasowitz Benson Torres.
Fox News, suffering under the weight of several previous sexual harassment claims, settlements and scandals, suspended Bolling over the weekend, pending the outcome of an investigation.
Ali was first to report that MSNBC was in talks to hire Hugh Hewitt and give him his own show, which it did.
Bolling has yet to comment on the lawsuit.
HuffPost also said it had "no hesitation" to financially stand by Ali, who is a paid freelancer under contract with the news organization. The network is also looking into a separate claim by frequent Fox News guest Caroline Heldman that Bolling sexually harassed her. FNC had previously been rocked by the forced resignations of its founder Roger Ailes and one of its most well-known on air personalities Bill O'Reilly under accusations of sexual harassment.
She said Ali's story had 14 sources.
Fox News has retained the services of Paul, Weiss, Rifkind, Wharton & Garrison, a prominent law firm with prior experience in handling legal cases in the entertainment industry, to head the investigation.
Others at Fox News later came forward with similar claims, and Ailes left the company on July 21, 2016. When Weiner pleaded guilty earlier this year to sending obscene material to an underage girl, Bolling said he was a "sick human being, to continue to do this time and time again".