In an August 7, 2013 opinion, Ackerman v. ExxonMobil Corp., the US Court of Appeals for the Fourth Circuit affirmed a district court's order abstaining from exercising jurisdiction under the Colorado River doctrine and 28 U.S.C. 1446(d), agreeing that the federal court should abstain from exercising jurisdiction in deference to pending, parallel state proceedings.

In June 2004, residents of a Maryland town filed a putative class action, captioned Koch, against the defendants in Maryland state court. In February 2010, the state court judge granted class certification, only to sua sponte rescind certification in June 2011. The state court judge asked the attorneys in the Koch matter to file a new action for the former class members, so that he could consolidate it with the Koch matter and therefore adjudicate all claims at once. This action was captioned Ackerman. On November 18, the judge informed parties that he planned to issue an order of consolidation.

On November 28, 2011, the defendants removed the Ackerman matter to federal district court. On December 1, the Koch plaintiffs amended their state court action to include all of the individual plaintiffs named in Ackerman. On the same day in federal court, the Ackerman plaintiffs filed a motion to remand or, in the alternative, to refrain from exercising jurisdiction in deference to the Koch action. The district court denied the motion to remand, but granted the motion to abstain under the Colorado River standard, which allows a federal court to abstain in favor of ongoing, parallel state proceedings. ExxonMobil maintained that the matters were not parallel at the time of removal, and appealed the district court's opinion.

On appeal, ExxonMobil argued that the state court was enjoined from making the December first amendment, conceding that the amendment made the actions parallel. ExxonMobil first argued that the amendment was void by operation of 28 U.S.C. § 1446(d), which deprives state courts of jurisdiction over matters once they are removed. The court rejected this argument, noting that only Ackerman was removed, so the state court maintained jurisdiction over and Koch.

ExxonMobil then argued that an exception to the Anti-Injunction Act, 28 U.S.C. § 2283, authorizes federal courts to use Section 1446(d) against separate "copycat" actions, which involve the same parties and claims and are filed in state court to defeat federal jurisdiction. Though the court noted that such authority might exist where the plaintiff fraudulently files a state suit to undermine the removal statutes, it determined that no fraud existed in Ackerman. The court therefore held that the state court acted properly in amending the complaint, and upheld the district court's decision to abstain.

Practitioners are reminded that Section 1446(d) only prevents state courts from exercising jurisdiction in matters that have been removed to federal court, and not on other potentially related actions.