John J. Sullivan


New York

(212) 453-3729

(646) 461-2073

Cherry Hill

(856) 910-5067

John practices in the firm's Commercial Litigation Department and has nearly two decades of experience handling a wide variety of complex litigation. He defends companies in securities, corporate governance, antitrust, product liability, class action, mass tort, and other business litigation. John regularly represents global companies in the life sciences, chemical, banking, venture capital, fund management, and real estate industries.  

In the real estate industry, John represents lenders, REITs, and financial trusts in high-stakes litigation and advisory work regarding workouts and distressed assets, including disputes between servicers and co-lenders, and contract matters relating to distressed borrowers.  John develops practical tactics for both negotiations and litigation relating to all types of distressed real estate disputes. 

In the area of financial litigation, John defends clients in state and federal courts in disputes involving contested takeovers, securities class actions, investigations by the SEC Division of Enforcement, contested mutual fund rights offerings, RICO claims, fraud claims in insurance company insolvency proceedings, and commercial real estate contract disputes. He often advises mutual funds and banks on litigation and regulatory issues.

John has also served on trial defense teams in some of the largest and most challenging product liability and mass tort litigation in the last decade. He has defended companies in coordinated proceedings involving claims of failure to warn, consumer fraud, manufacturer and design defect, and warranty and breach of contract.

A well-rounded commercial litigator, John has deep experience managing attorneys conducting case-specific discovery, defending witnesses, handling evidentiary and coordination hearings, negotiating with opponents, and deposing and defending expert witnesses. He has litigated constitutional and preemption issues, dealt with regulatory agencies and their regulations, and represented clients in appellate proceedings before state and federal appellate courts, including the United States Supreme Court.

Before joining Cozen O’Connor John was a partner Dechert LLP, and he started his career at Sullivan & Cromwell. For John's considerable success, he has been recognized by Benchmark Litigation as a “future star” in their 2009 and 2010 editions and an “innovative lawyer” by the Financial Times in 2011.

John is a frequent author and speaker at legal conferences, and he is often asked to comment on current litigation in the legal media. He is an author of the Class Action Defense Review, as well as the Drug & Device Law Blog, one of the most well-respected product liability litigation blogs.

John earned his law degree from Rutgers School of Law-Newark, where he was awarded the Order of the Coif and was a two-time Saul Tischler Scholar. He received his bachelor's degree from Rutgers University, New Brunswick.



17 Cozen O’Connor Attorneys Recognized as New York Super Lawyers and Rising Stars

September 27, 2019

Super Lawyers has named 17 Cozen O'Connor attorneys to its 2019 New York Super Lawyers and Rising Stars list.

FDA Alert on Hacking Vulnerability in Heart Defibrillators is Wake-Up Call: Lawyers

March 28, 2019

John Sullivan was quoted in Law360's recent article on the U.S. Food and Drug Administration's recent safety alert last week about the vulnerability to hacking of up to 750,000 implantable heart defibrillators.

18 Cozen O'Connor Attorneys Named New York Metro Super Lawyers and Rising Stars

September 21, 2018

Super Lawyers has named 17 Cozen O'Connor attorneys to its 2018 New York Super Lawyers and Rising Stars list. Twelve were recognized as Super Lawyers and five were named "Rising Stars."

Texas Suit Over Death Penalty Drug Faces Steep Odds

May 10, 2017

John Sullivan, a member of Cozen O'Connor's Commercial Litigation department, discusses Texas's uphill battle against the U.S. Food and Drug Administration in its suit over the agency’s import ban of a drug used to carry out lethal injection executions.

Huge Verdicts Won't Spur Settlement Talks In J&J Hip MDL

December 02, 2016

John Sullivan, a member of Cozen O'Connor's Commercial Litigation department, discusses the recent Johnson & Johnson case in Law360.

J&J Faces Hip MDL Trial Amid Series Of Pro-Plaintiff Rulings

September 30, 2016

John Sullivan, a member of Cozen O'Connor's Commercial Litigation department, discusses this case in Law360.

Cozen O'Connor Grows Litigation Team in New York with Five New Partners

October 15, 2013

Cozen O’Connor continues to increase the depth of the firm’s litigation capabilities in New York with the recent hiring of five new partners. Partners residing in the firm's New York office who have joined in recent months include John J. Sullivan, Michael B. de Leeuw, Patrick B. Sardino, William K. Kirrane and Adam I. Stein.


The Canary in the Coal Mine Isn’t Looking So Good Anymore

December 04, 2018

John Sullivan, a member of the firm's Commercial Litigation Department, authored the blog, "The Canary in the Coal Mine Isn’t Looking So Good Anymore" for the Drug & Device Law blog.

MDL Court in the Testosterone Replacement Therapy Litigation Throws Out Another Large Jury Verdict

July 13, 2018

John Sullivan, a member in the firm's Commercial Litigation Practice, authored, "MDL Court in the Testosterone Replacement Therapy Litigation Throws Out Another Large Jury Verdict," for the Drug & Device Law Blog.

Personal Jurisdiction through Alter Ego Fails in Illinois

June 29, 2018

John Sullivan, a member in the firm's Commercial Litigation Practice, authored, "Personal Jurisdiction through Alter Ego Fails in Illinois" for the Drug and Device Law Blog.

New York Court of Appeals Rejects Litigation Science under Frye Standard [Products Liability Prevention & Defense Blog]

March 08, 2016

Put quotes around the phrase “litigation science” and Google it.  Go ahead, we’ll wait. . . . . What did you find?  Not good, right.  You found a lot.  Too much.  The first Google page alone shows how controversial this subject is.  For instance, you’ll find references to Ninth Circuit Judge Alexi...

Should We Expand the Collateral Source Rule? No Thanks [Drug and Device Law]

October 26, 2015

John Sullivan discusses the Louisiana Supreme Court case Hoffman v. 21st Century North Am. Ins. Co., in which the plaintiff attempted to expand the collateral source rule to allow recovery of medical costs that were never actually billed.

MDL Judge Allows Manufacturing Defect Claim to Go to Trial with No Direct Evidence of a Defect in the Device Actually Implanted in Plaintiff [Drug and Device Law]

October 19, 2015

John Sullivan discusses In re Mentor Corp. ObTape Transobturator Sling Prods. Liability Litigation, in which the court relied solely on a review conducted by plaintiff’s experts of sample ObTape devices (other than the one implanted in plaintiff) when denying the manufacturer’s motion for summary judgment.

Court Interprets North Carolina Law to Apply the Learned Intermediary Doctrine to Medical Device Cases [Drug and Device Law]

October 12, 2015

John Sullivan discusses Carlton v. Boston Scientific Corp., in which the court granted Boston Scientific summary judgment.

Section 510(k) Clearance: While it Doesn't Support Preemption, is it Relevant Evidence at Trial? [Drug and Device Law]

September 28, 2015

John Sullivan discusses Boston Scientific Pelvic Repair System Products Liability Litigation and how the 510(k) clearance of a medical device is not only insufficient to support preemption, but it’s not probative enough to be discussed at trial.

Eli Lilly Successfully Severs and Transfers Cymbalta Plaintiffs from California Court to Its Own Home Court in Indiana [Drug and Device Law]

September 22, 2015

John Sullivan discusses the recent Cymbalta litigation in which the plaintiffs tried and failed to create an MDL.

Winning Product Liability Cases with Particularly Devastating Injuries [Products Liability Prevention & Defense Blog]

September 14, 2015

In product liability litigation, many of the cases involve horrible things that have happened to good people. Often they then sue a company looking to assess blame and receive some form or compensation or satisfaction. At first blush, that’s more than understandable. But often times the defendant...

The Flood Gates Are Open: Amarin’s Win Spurs Another First Amendment Challenge to the FDA’s Regulation of Off Label Promotion [Drug and Device Law]

September 14, 2015

John Sullivan discusses Pacira Pharmaceuticals’ recent First Amendment challenge on their non-opioid pain drug, EXPAREL, in the wake of Amarin’s preliminary injunction win.

The Amarin Win and the Next Big Question: What Will the FDA Do? [Drug and Device Law]

August 17, 2015

John Sullivan discusses Amarin’s successful motion for a preliminary injunction in its First Amendment challenge to the FDA’s regulation of off-label marketing and discusses what this means for the FDA.

The District of New Jersey Holds That You Can’t “Discover” Your Way to a Parallel Violation Claim [Drug and Device Law]

August 10, 2015

John Sullivan discusses Becker v. Smith & Nephew, a hip implant case pending in federal court in New Jersey.

Court of Common Pleas Leaves Standing Janssen’s Victory in Second Risperdal Trial [Drug and Device Law]

July 13, 2015

John Sullivan discusses the second Risperdal trial, Cirba v. Janssen Pharmaceuticals, Inc., in which the trial judge denied the plaintiff’s post-trial motion for a new trial.

The Court Will Hear Oral Argument Tomorrow Morning on Amarin's First Amendment Challenge to FDA Off-Label Regulation [Drug and Device Law]

July 06, 2015

John Sullivan discusses the completed briefing on Amarin's motion for preliminary injunction and the courts preparation to hear oral arguments from the FDA and Amarin.

The FDA Sends Amarin A Letter In Their First Amendment Court Battle [Drug and Device Law]

June 22, 2015

John Sullivan discusses the ongoing First Amendment case between Amarin Pharma, Inc. and the FDA.

Second Circuit Casts Doubt on Viability of Off-Label Claims in Device Cases [Drug and Device Law]

June 15, 2015

John Sullivan discusses Otis-Wisher v. Medtronic Inc., in which the Second Circuit offered its thoughts on the viability of parallel violation claims based on allegedly misleading off-label promotion.

If You Can’t Show Fraudulent Joinder, You May Still Be Able to Sever Non-Diverse Defendants Using FRCP 21 [Drug and Device Law]

June 08, 2015

John Sullivan discusses Mayfield v. London Women's Care, PLLC, in which a patient, who had revision surgery and other complications, sued the out-of-state manufacturers and named her local doctor and his clinic as malpractice defendants.

Bausch Strikes Again [Drug and Device Law]

June 01, 2015

John Sullivan discusses the ruling in Dwyer v. Boston Scientific Corp., in which a man died from head injuries suffered during a fall after the failure of his implanted defibrillator.

Another Municipality Tries to Recover Its Costs for Pharmaceuticals [Drug and Device Law]

May 18, 2015

John Sullivan discusses City of Chicago v. Purdue Pharma L.P., which deals with an effort by the city of Chicago to recover payments it made to drug companies on opioid prescriptions for city employees (and retirees) covered by HMO, PPO and worker's compensation plans.

Amarin v. FDA Focuses the Spotlight on the First Amendment and the FDA's Regulation of Off-Label Promotion [Drug & Device Law]

May 11, 2015

John Sullivan discusses Amarin Pharma, Inc. v. FDA, in which Amarin seeks a declaration that the FDA's off-label regulations, as applied by the FDA, violate the First Amendment and the Due Process clause of the Fifth Amendment.

Yes, There Is Still Vioxx Litigation [Drug and Device Law]

April 27, 2015

John Sullivan discusses Levitt v. Merck Sharp & Dohme Corp., in which the Vioxx MDL court denied Merck's motion for summary judgment, instead ordering that discovery be reopened.

You Want to Remand? I'm Already Gone [Drug and Device Law]

April 20, 2015

John Sullivan discusses Cole v. Medtronic, Inc., in which the plaintiff asked the court to remand the case back to state court because a second defendant, a hospital, was a citizen of the forum state, thus triggering the forum-defendant rule and blocking removal.

The Next Best Thing to Mensing Preemption: Winning for Lack of Connection between Marketing and the Prescriber [Drug and Device Law]

April 13, 2015

John Sullivan discusses Whitener v. Pliva, in which the claim states that the manufacturer didn't warn about risks of the drug, in this instance, off-label risks.

Limiting the Damage from One-Sided Ex Parte Interviews of Doctors [Drug and Device Law]

March 30, 2015

John Sullivan discusses Yotam v. Takeda Pharmaceuticals North America, Inc. and the uneven ground of ex parte interviews of treating doctors, an area in which plaintiffs' counsel too often seem to be handed the higher ground.

Zogenix's Battle with the Commonwealth of Massachusetts Continues [Drug and Device Law]

March 23, 2015

John Sullivan discusses the latest decision in Zogenix, Inc. v. Baker, in which the Commonwealth of Massachusetts has tried to regulate Zohydro ER, an extended release hydrocodone drug product that was approved by the FDA in 2013.

The Treatment of Confidential Material Across Collateral Litigation [Drug and Device Law]

March 16, 2015

John Sullivan discusses collateral litigation and companies who find themselves in difficult court battles to protect confidential, business-sensitive information from public disclosure.

A Victory Well Won [Drug and Device Law]

March 09, 2015

John Sullivan discusses Lewis v. Johnson & Johnson, in which the defendant calmly and effectively pressed their legal and factual arguments, won a partial victory before trial, continued to press its position on the law and facts at trial until it won a direct verdict, and successfully had it all upheld on appeal.

Statistics Are Still Unnecessary For A Label To Be Adequate [Drug and Device Law]

March 02, 2015

John Sullivan discusses McDowell v. Eli Lilly, in which plaintiff motioned for reconsideration, only to have the judge state the product's label contained sufficient warning and upheld judgment for the defendant.

‘Irreparable Harm’ Is a Tough Hurdle to Clear [New York Law Journal]

February 23, 2015

In an article titled '''Irreparable Harm' Is a Tough Hurdle to Clear,'' Michael de Leeuw and John Sullivan, members of Cozen O'Connor's Commercial Litigation Department, examine the current state of preliminary injunction jurisprudence in New York courts (with liberal reference to their federal counterparts), in particular the treatment of the “irreparable harm” branch of the test, and explore whether there are any better guiding standards that might make preliminary injunction practice more predictable.

Halliburton Decided! World Does Not End [Class Action Defense Review Blog]

June 23, 2014

This morning the Supreme Court released its highly-anticipated decision in Hallburton Co. v. Erica P. John Fund, Inc.  As we (and, to be fair, others) predicted after the oral argument, the Court did not have the appetite to overturn Basic Inc. v. Levinson (though Justices Thomas, Scalia and Alito...

How To Clean Up Against Washing Machine Class Actions [Law360]

May 12, 2014

John J. Sullivan, member of Cozen O’Connor’s Litigation Department, and Christopher Passavia, associate in Cozen’s Litigation Department, co-authored an article titled “How to Clean Up against Washing Machine Class Actions,” in which they discuss the difficulties presented when defending against such lawsuits. Sullivan and Passavia offer their advice, based on various Washing Machine Class Actions cases, on what steps can be taken by the defense.

New Jersey District Court Cleans Up Complaint in Washing Machine Class Action Litigation [Class Action Defense Review Blog]

April 14, 2014

Washing machine class actions have been so active recently that some firms may be scrambling to form their own appliance-law practice groups.  And who knows?  That might not be a bad idea.  Some of our greatest legal minds, like Judge Posner, have been weighing in on this litigation.  In two of his...

Back to Basic? Big Changes Could Be Coming to a Securities Class Action Near You [Class Action Defense Review Blog]

March 26, 2014

Earlier this month, the Supreme Court heard the highly-anticipated oral argument in Hallburton Co. v. Erica P. John Fund, Inc.  Prior to the argument, there was a growing consensus that the Court was likely going to overturn Basic Inc. v. Levinson (1988), the groundbreaking case that adopted the...

8th Circ. Suggests More Mass Torts May Be Removable [Law360]

January 03, 2014

The Eighth Circuit recently upheld the removal to federal court of product liability claims filed by over 100 plaintiffs in state court in St. Louis. See Atwell v. Boston Scientific Corp., 2013 (8th Cir. Nov. 18, 2013). The decision illustrates how plaintiffs’ requests to coordinate multiple cases can sometimes sweep “mass tort” cases filed in state court right into federal court as a “mass action” under the Class Action Fairness Act of 2005. This is no small shift in a litigation, and so Atwell provides a helpful background on some of the characteristics of a plaintiff coordination proposal that can trigger such CAFA removal.

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  • Rutgers University School of Law—Newark, J.D., 1996
  • Rutgers University, New Brunswick, B.A., 1992

Awards & Honors

Best Lawyers in America 2018

New York Super Lawyer in Business Litigation 2018, 2019

  • New York
  • New Jersey
  • U.S. Supreme Court
  • U.S. Court of Appeals for the Second Circuit
  • U.S. District Court -- New Jersey
  • U.S. District Court -- Southern District of New York
  • U.S. District Court -- Eastern District of New York