(WILMINGTON, Del.) — Attorneys representing Hunter Biden filed his answer and counterclaims alleging invasion of privacy in response to a defamation lawsuit brought by the Delaware-based computer repairman who they say triggered the infamous laptop controversy in the weeks leading up to the 2020 presidential election.

The step represents a major escalation in the younger Biden’s increasingly aggressive legal posture toward some of his most vocal critics and those who allegedly trafficked his personal information.

The suit, filed in a Delaware federal court, targets John Paul Mac Isaac, a computer repairman who in April 2019 purportedly obtained and later disseminated data from a laptop allegedly belonging to the president’s son. The counterclaim is in response to a defamation lawsuit filed by Mac Isaac against Hunter Biden and others in October 2019, which is ongoing.

“[Hunter] Biden had more than a reasonable expectation of privacy that any data that he created or maintained … would not be accessed, copied, disseminated, or posted on the Internet for others to use against him or his family or for the public to view,” according to the countersuit.

Attorneys for Hunter Biden challenged Mac Isaac’s claim that the laptop and an external hard drive became his property when Hunter Biden failed to retrieve them within 90 days of leaving them at the repairman’s Wilmington, Delaware, shop for servicing, citing the fine print of a repair order allegedly signed by Hunter Biden at the time.

“Contrary to Mac Isaac’s Repair Authorization form, Delaware law provides that tangible personal property is deemed abandoned” when the rightful owner has failed to “assert or declare property rights to the property for a period of 1 year,” lawyers for Biden wrote in legal documents.

The counterclaim adds that “other obligations must then also be satisfied before obtaining lawful title, such as the court sending notice to the owner and the petitioner posting notice in five or more public places, and advertising the petition in a newspaper.”

Hunter Biden is seeking a jury trial and unspecified “compensatory damages” from Mac Isaac. A lawyer for Mac Isaac did not immediately respond to a request for comment.

Friday’s counterclaim is the latest turn in an increasingly offensive legal tack from the younger Biden, who until recently had largely avoided public confrontations about his business dealings.

In recent months, a revamped legal team led by well-known criminal defense attorney Abbe Lowell has penned a flurry of cease-and-desist letters on Hunter Biden’s behalf, and has threatened litigation against some of his most vocal critics, including Mac Isaac.

The computer repairman emerged as a central figure in the drama surrounding Hunter Biden’s laptop in the waning days of the 2020 presidential campaign, when images, emails, and text messages allegedly belonging to Hunter Biden emerged in public and galvanized the national conversation as voters took to the polls.

According to accounts given by Mac Isaac and his attorney, on April 12, 2019, Hunter Biden arrived at Mac Isaac’s computer repair shop with three damaged devices and asked if the data could be recovered. Days later, Mac Isaac said, he asked Hunter Biden to return to the shop to retrieve the devices and pay an $85 service fee. Mac Isaac has said he never heard back from Hunter Biden, and the invoice was never paid.

After 90 days, according to Mac Isaac and his attorney, the abandoned laptop became Mac Isaac’s property, pursuant to the work order agreement Hunter Biden allegedly signed when he first visited Mac Isaac’s shop.

Mac Isaac subsequently turned the laptop and external hard drive over to the FBI in December 2019, and later sought to share information from the devices with then-President Donald Trump’s personal attorney, Rudy Giuliani, who made the contents of the devices available to other Trump allies and some news outlets in the weeks prior to the 2020 presidential election.

ABC News has not reviewed nor verified the contents of the laptop or hard drive.

Mac Isaac initially sued Hunter Biden for defamation, alongside Rep. Adam Schiff, Politico, and CNN, in Delaware state court. Earlier this month the case was moved to the U.S. District Court in Delaware, where Hunter Biden filed his counterclaim.

In their countersuit, attorneys for Hunter Biden disputed Mac Isaac’s claim to have acted both legally and responsibly with data found on the laptop and hard drive.

“Reputable computer companies and repair people routinely delete personal data contained on devices that are exchanged, left behind or abandoned,” the lawyers wrote. “They do not open, copy, and then provide that data to others, as Mac Isaac did here.”

In addition to providing copies to the FBI and Giuliani, Mac Isaac sought to distribute copies of the contents of the laptop and hard drive to several allies of the former president, including Republican lawmakers, and Fox News host Tucker Carlson, he said.

The countersuit draws heavily from Mac Isaac’s own writings and public commentary regarding his intentions in sharing the data, accusing the repairman of being motivated by his preference of Donald Trump over Joe Biden in the 2020 election.

Lawyers for Hunter Biden wrote that “Mac Isaac intended and knew, or clearly should have known, that people to whom he provided the data that he believed to belong to Mr. Biden would use it against then-candidate Joseph Biden and to assist then-President Trump.”

This new legal offensive comes as congressional scrutiny of President Biden’s family ramps up and federal prosecutors press forward in their yearslong probe of Hunter Biden’s tax affairs and overseas business endeavors.

Hunter Biden has repeatedly said he is cooperating with federal investigators and remains “100% certain” that he will be cleared of any wrongdoing. President Biden has said he and his son never discussed his foreign business dealings, and there are no indications that the federal investigation involves the president in any way. The White House has repeatedly sought to distance the president from the Justice Department probe.

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