This post will be a running aggregation of pending "natural born citizen" challenges in the 2016 presidential election. Please feel free to post updates in the comments about other pending challenges.
The bulk of challenges center around Senator Ted Cruz, born in Canada to a Cuban father an an American mother. There are other challenges (including those regarding Bobby Jindal, Marco Rubio, and Rick Santorum), but they are more obscure (indeed, Messrs. Jindal and Santorum have dropped out). Additionally, there are administrative challenges to candidates' eligibility to appear in a primary (e.g., whether Donald Trump is a "Republican" or whether Bernie Sanders is a "Democrat") or whether candidates have met the ballot access requirements (e.g., whether a candidate has met the requisite number of signatures to appear on the ballot). Those are not included below.
Please feel free to include updates or links in the comments below, or contact me via Twitter.
An * preceding the case means a final judgment has not yet been entered.
Board of Election or Secretary of State Administrative Challenges
Joyce v. Cruz (160SOEBGP526), Graham v. Cruz (16SOEBGP527), Graham v. Rubio (16SOEBGP528): decision
Indiana, Election Commission
Carter v. Rubio (Cause 2016-2), Carter v. Cruz (Cause 2016-3), Kern v. Cruz (Cause 2016-4): decision permitting appearance on ballot, not yet available electronically, news story here
Elliot v. Cruz, Booth v. Cruz (BLC 2015-2): decision
Laity v. Cruz, Laity v. Rubio (BLC 2015-4): decision
New York, Board of Elections
Booth v. Cruz (D.N.H. 15–cv–518): dismissed (Feb. 2, 2016)
Voeltz v. Cruz (Broward County, Fla. Circuit Ct. CACE15022044): docket, dismissed (March 4, 2016)
Smallwood v. State (Hawaii Supreme Ct. SCEC–16–0000330): dismissed (Apr. 21, 2016)
Korman v. New York State Board of Elections (New York County, Supreme Ct. 100240/2016): memorandum of law; dismissed (Mar. 7, 2016); affirmed on appeal (Mar. 24, 2016); appeal denied (Mo. No. 2016-374, Apr. 1, 2016)
Farrell v. Cruz (Pennsylvania): dismissed (Mar. 11, 2016), news stories here and here; appeals to Supreme Court (29 MAP 2016), affirmed (Mar. 31, 2016); *petition for certiorari filed sub nom. Elliott v. Cruz (16-13)
Paige v. Vermont (Washington Civil Div., Vt. Sup. Ct. 780-12-15 Wncv): complaint; dismissed (May 12, 2016)