A federal judicial panel has transferred more than 40 class actions involving a data breach that ensnared Quest Diagnostics to New Jersey, near the headquarters of the medical testing company.

The U.S. Judicial Panel on Multidistrict Litigation ordered the transfer Wednesday of all the lawsuits, brought over a breach of data at American Medical Collection Agency Inc., a billing collection service. The breach compromised the private information of more than 20 million people, including 11.9 million patients at Quest Diagnostics Inc. and 7.7 million at Laboratory Corp. of America, based in Burlington, North Carolina.

In its order, the panel transferred the cases to U.S. District Judge Madeline Cox Arleo of the District of New Jersey. Quest Diagnostics, Laboratory Corp. of America and two other companies named as defendants in the lawsuits, New Jersey’s Bio-Reference Laboratories Inc. and UnitedHealth Group’s Optum360 Services Inc., a Quest billing contractor in Minnesota, had supported the New Jersey venue and Arleo. American Medical Collection Agency, based in Elmsford, New York, did not appear before the MDL and filed for Chapter 11 bankruptcy June 17.

“All defendants and plaintiffs in over a dozen actions support this district, where four actions on the motion and seven potential tag-along actions are pending,” wrote MDL panel Chairwoman Sarah Vance. “Defendants Quest and Bio-Reference have their headquarters there, and AMCA is located nearby in Elmsford, New York. Thus, common documents and witnesses likely will be located in or near this district.”

Quest Diagnostics attorney David Hoffman of Sidley Austin and Allison Holt Ryan of Hogan Lovells, a lawyer for Laboratory Corp. of America, did not respond to requests for comment. Bio-Reference attorney Paul Karlsgodt of Baker & Hostetler and Kristine McAlister Brown of Alston & Bird, for Optum360, also did not respond, nor did a representative of American Medical Collection Agency.

Plaintiffs attorneys Linda Nussbaum of New York’s Nussbaum Law Group and Chris Seeger of Seeger Weiss had moved to transfer the cases to New Jersey last month.

“The panel decision was very well reasoned and there are efficiencies to be had by transferring all of the cases to J[udge] Arleo, who is an experienced and creative judge who is very well suited to organize and preside over these important cases,” wrote Nussbaum in an email.

A competing plaintiffs attorney, Tina Wolfson of Ahdoot & Wolfson, had moved to transfer the cases to the Southern District of New York, while others pushed for the Central District of California.

In an unusually detailed order, the panel rejected an attempt from some plaintiffs attorneys to create multiple MDLs based on various laboratories.

“In many situations,” Vance wrote for the panel, “we are hesitant to bring together actions involving competing defendants, but when, as here, the actions stem from the same data breach, and there is significant overlap in the central factual issues, parties, proposed classes, and claims, we find that creation of a single MDL is warranted.”

The lawsuits followed Quest Diagnostics’ June 3 announcement of the breach, which compromised financial data, Social Security numbers and medical information. Attorneys general in Connecticut and Illinois have opened investigations into the breach, which now involves hundreds of thousands more customers of several more medical companies.

Separately, on Wednesday, the MDL panel sent two groups of cases to U.S. District Judge Leonard Stark of the District of Delaware. One MDL involves half a dozen patent infringement cases that Keryx Biopharmaceuticals Inc. brought over generic Auryxia, used to treat chronic kidney disease. The other MDL is comprised of five antitrust class actions focused on another drug used to treat chronic kidney disease: Amgen’s Sensipar.