Does a second-in-time habeas filing qualify as a “second or successive application” under 28 U.S.C. § 2244(b) if the judgment denying the first petition is still under review on appeal? This question determines whether such a filing must satisfy the stringent gatekeeping requirements of the Antiterrorism and Effective Death Penalty Act of 1996 (AEDPA). Specifically, the Court must decide if the dividing line between an initial and a successive application is the entry of district court judgment or the conclusion of appellate review.

• The second filing should not trigger § 2244(b) because the first petition was still pending on appeal when the second was filed.
• Treating the second filing as an amendment rather than a new application advances AEDPA's goals by allowing district courts to use their tools to hasten finality.
• Historical habeas doctrine and practice support the view that filings during a pending appeal should not be barred as successive.
• Alternatively, a motion to amend under Federal Rule of Civil Procedure 15 is not an "application" by its nature and thus falls outside § 2244(b).

• The Court lacks jurisdiction because the petitioner lacks standing since the Fifth Circuit already affirmed the initial judgment.
• Habeas jurisdiction is absent because the petitioner is no longer in custody on the specific child-pornography conviction challenged in the second filing.
• Entry of final judgment by the district court, not the conclusion of appellate review, is the correct dividing line for identifying "second or successive" applications under § 2244(b).

• The Court held that once a district court enters its judgment on a first habeas petition, any second-in-time filing qualifies as a “second or successive application” subject to 28 U.S.C. § 2244(b).
• The Court defined "second or successive application" as a term of art under § 2244(b)(2), where an "application" is a filing seeking an adjudication of a "claim" (an asserted federal basis for relief) on the merits, citing *Gonzalez v. Crosby* and *Woodford v. Garceau*.
• The Court reasoned that while amended petitions filed before judgment are not successive, motions under Federal Rule of Civil Procedure 60(b) filed after judgment generally are if they attack a previous resolution or add new grounds for relief (*Gonzalez*).
• It distinguished *Banister v. Davis*, noting that Rule 59(e) motions are unique because they "suspend finality" and help produce a single final judgment, whereas the petitioner's filing collaterally attacked an already completed judgment.
• The Court invoked the purpose of AEDPA—to "conserve judicial resources, reduce piecemeal litigation, and lend finality to state court judgments"—reasoning that drawing the line at the end of appeals would encourage inefficient, piecemeal litigation.
• It rejected the petitioner's historical argument, finding that pre-AEDPA practice was too inconsistent and "murky" to be dispositive.
• The Court declined to rule on the Rule 15 amendment theory because it was not raised in the petition for certiorari and lacked a factual predicate since the District Court lacked jurisdiction while the case was on appeal (*Coinbase, Inc. v. Bielski*).