SUMMARY ORDER

Petitioner Michael Noel Anthony Hammond, a native and citizen of Jamaica, seeks review of a July 25, 2016 decision of the BIA denying his June 2016 motion to reconsider his 2003 removal order. In re Michael Noel Anthony Hammond, No. A037 215 537 (B.I.A. July 25, 2016). We assume the parties’ familiarity with the underlying facts and procedural history in this case.

A motion to reconsider must be filed within 30 days of the challenged order. 8 U.S.C. § 1229a(c)(6)(A)-(B); 8 C.F.R. § 1003.2(b). It is undisputed that Hammond’s June 2016 motion to reconsider was untimely because his removal order became final in 2003, 13 years earlier. 8 Ú.S.C. § 1229a(c)(6)(B). Here, reconsideration was available only under the BIA’s sua sponte authority. 8 C.F.R. § 1003.2(a). Despite this procedural posture, we retain jurisdiction to review Hammond’s U.S. citizenship claim. Duarte-Ceri v. Holder, 630 F.3d 83, 87 (2d Cir. 2010). We review the derivative citizenship claim de novo, deferring to the BIA’s reasonable interpretation of ambiguous provisions of the Immigration and Nationality Act (“INA”). Brissett v. Ashcroft, 363 F.3d 130, 133 (2d Cir. 2004); see also Chevron U.S.A. v. Natural Res. Def. Council, 467 U.S. 837, 843, 104 S.Ct. 2778, 81 L.Ed.2d 694 (1984).

In determining whether Hammond derived citizenship through his mother’s naturalization, we look to the law in effect at the time Hammond claims he fulfilled the last requirement for derivative citizenship. Bueno Gil v. Sessions, 851 F.3d 184, 186 (2d Cir. 2017). In 1987, when Hammond’s mother naturalized, the law governing derivative citizenship provided in relevant part:

A child born outside of the United States of alien parents ... becomes a citizen of the United States upon ... [t]he naturalization of the parent having legal custody of the child when there has been a legal separation of the parents ... if ... [s]uch naturalization takes place while such child is under the age' of eighteen years.

8 U.S.C. § 1432(a) (1987), repealed by Child Citizenship Act of 2000, Pub. L. 106-395, §103, 114 Stat. 1631, 1632 (2000).

The only issue in this case is whether Hammond’s parents were legally separated in 1987, when his mother naturalized. See Brissett, 363 F.3d at 132. Legal separation under § 1432(a)(3) requires more than a de facto separation between married parents: it' “requires a formal act which, under the laws of the state or nation having jurisdiction of the marriage, alters the marital relationship either by terminating the marriage (as by divorce) or by mandating or recognizing the separate existence of the marital parties.” Id. at 134.

Hammond argues that his parents were legally separated under Jamaica’s Matrimonial Causes Act. See Matrimonial Causes Act (Jamaica) (Jan. 6,1989). As the Government argues, the Matrimonial Causes Act did not take effect until 1989, and thus it cannot provide a basis for a legal separation pre-dating Hammond’s mother’s naturalization in 1987 or Hammond’s 18th birthday in 1988. Furthermore, Hammond has not raised a genuine issue of material fact as to whether his parents took formal action to have their separation recognized under the Act or any other Jamaican law. We thus uphold the BIA’s conclusion that Hammond did not meet § 1432(a)(3)’s legal separation requirement and so did not derive U.S. citizenship when his mother naturalized.

For the foregoing reasons, the petition for review is DENIED. It is further ORDERED that Hammond’s motion to proceed in forma pauperis is DENIED as moot. Any pending request for oral argument in this petition is DENIED in accordance with Federal Rule of Appellate Procedure 34(a)(2), and Second Circuit Local Rule 34.1(b).