NOT PRECEDENTIAL

                      UNITED STATES COURT OF APPEALS
                           FOR THE THIRD CIRCUIT
                                ___________

                                     No. 10-3197
                                     ___________

                                     ERIC DAVIS,
                                            Appellant

                                            v.

                                  T.R. SNIEZEK
                      ____________________________________

                    On Appeal from the United States District Court
                       for the Middle District of Pennsylvania
                         (D.C. Civil Action No. 10-cv-00740)
                      District Judge: Honorable Edwin M. Kosik
                     ____________________________________

                   Submitted Pursuant to Third Circuit LAR 34.1(a)
                                 December 7, 2010

       Before: FUENTES, GREENAWAY, JR. and NYGAARD, Circuit Judges

                          (Opinion filed December 10, 2010 )

                                     ___________

                                      OPINION
                                     ___________

PER CURIAM

      Eric Davis appeals pro se from the District Court’s order denying his petition for a

writ of habeas corpus under 28 U.S.C. § 2241. We will affirm.

                                            I.
       Davis contends that the Bureau of Prisons (“BOP”) has miscalculated his sentence

by refusing to credit him for certain time served. Davis was in Maryland state custody

when, on December 5, 2005, a Maryland state court sentenced him to five years of

imprisonment (less time served) for a state parole violation. A federal indictment also

had been filed against him. On December 16, 2005, the United States District Court for

the District of Maryland issued a writ of habeas corpus ad prosequendum to compel his

appearance to answer the federal charges. A United States Marshal executed the writ and

took him into federal custody on January 6, 2006. That same day, a federal Magistrate

Judge entered an order of detention on the federal parties’ agreement without prejudice to

their ability to challenge the federal detention.

       Davis remained in federal custody for the duration of his federal proceeding.

During that time, his Maryland state sentence expired on September 12, 2008. Davis

ultimately pleaded guilty to the federal charges, and the Maryland District Court

sentenced him to 168 months of imprisonment on December 18, 2008. The United States

Marshal Service, unaware that Davis had completed his Maryland state sentence, returned

him to state custody on January 16, 2009. The Maryland Department of Corrections soon

discovered that his state sentence had expired and released him on January 21, 2009.

Davis surrendered to federal authorities to begin serving his federal sentence that day.

       The BOP later calculated Davis’s federal release date. In doing so, it determined

that his federal sentence commenced on January 21, 2009, when he surrendered to federal

authorities. It did not give him credit for time served between the date he was taken into

federal custody (January 6, 2006) until the date his state sentence expired (September 13,
2008), because it deemed him to remain in primary state custody during that time. It did

give him credit from the expiration of his state sentence to the date he surrendered to

federal authorities to begin his federal sentence.

        Davis, now incarcerated within the Middle District of Pennsylvania, filed a § 2241

habeas petition asserting that the BOP should have given him credit for the earlier period

as well. A Magistrate Judge recommended that the District Court deny the petition,

which it did by order entered July 6, 2010. Davis appeals.1

                                              II.

        The District Court concluded that Davis is not entitled to credit against his federal

sentence from the time he was taken into temporary federal custody until the time his

state sentence expired because that time already has been credited against his state

sentence (thus resulting in its expiration). For the reasons adequately explained by the

Magistrate Judge and District Court, we agree. See 18 U.S.C. § 3585(b) (permitting

credit only for time served “that has not been credited against another sentence”); see also

(§ 3585(b) does not permit “double credit” toward state and federal

sentence); Rios v. Wiley, 

, 271-73 (3d Cir. 2000) (same), superseded in part

by statute on other grounds as stated in United States v. Saintville, 

, 249 (3d

Cir. 2000).

        1
1.
      A certificate of appealability is not required to appeal the denial of a challenge to
     the execution of a sentence under § 2241. See Burkey v. Marberry, 

,
     146 (3d Cir. 2009). Thus, we have jurisdiction under 28 U.S.C. §§ 1291 and 2253.
     See Vega v. United States, 

, 313-14 (3d Cir. 2007). We review the
     District Court’s denial of habeas relief de novo and exercise plenary review over
     its conclusions of law. See 

       Davis does not directly contest that the first portion of his federal custody was

counted toward his state sentence. Instead, he argues that the State of Maryland

relinquished its jurisdiction over him when it surrendered him to federal authorities

pursuant to the writ ad prosequendum and that he should be deemed to have been in

exclusive federal custody since that date. Taking his argument one step farther than he

does, that would mean either that the State of Maryland expects him to serve the

remainder of his state sentence after his release from federal custody (which would result

in the same period of incarceration he now faces) or that it effectively pardoned him.

       We are not persuaded. A state prisoner transferred to federal custody under a writ

ad prosequendum to answer federal charges is considered “on loan” to federal authorities

and remains in primary custody of the state “unless and until the first sovereign

relinquishes jurisdiction.” Ruggiano v. Reish, 

, 125 n.1 (3d Cir. 2002),

superseded in part on other grounds by U.S.S.G. § 5G1.3 App. Note 3(E) (2003); 

. “Generally, a sovereign can only relinquish primary jurisdiction in one

of four ways: (1) release on bail; (2) dismissal of charges; (3) parole; or (4) expiration of

sentence.” United States v. Cole, 

, 897 (8th Cir. 2005).

       Davis does not argue that his sentence had expired or that the State of Maryland

did any of these things when it released him into temporary federal custody. Instead, he

argues that the State of Maryland’s intent to relinquish jurisdiction can be gleaned from

four factors. First, he argues that the federal parties “understood” that the January 6, 2006

detention order placed him in primary federal custody. Second, he argues that Maryland

District Court remanded him to the custody of the BOP rather than the State of Maryland
after it imposed his federal sentence. Third, he argues that federal authorities never

placed a detainer on him before erroneously transferring him back to the custody of the

State of Maryland. Finally, he argues that the State of Maryland did not contact federal

authorities before releasing him after determining that his state sentence had expired.

       None of these factors suggests that the State of Maryland intended to relinquish its

jurisdiction before Davis’s sentence expired. Instead, the only conclusion permitted by

the record is that the State of Maryland’s jurisdiction became extinguished by operation

of law on September 13, 2008, when his state sentence expired. See 

. The BOP properly credited all of his custody after that date against his federal

sentence, and he is entitled to nothing more. See 

n.1 (“For the

purposes of computing [a defendant’s] sentence . . . the time spent in custody pursuant to

a writ ad prosequendum is credited toward his state sentence, not his federal sentence.”).

       Accordingly, we will affirm the judgment of the District Court.