Who can initiate an optional referendum at the national level?

FEDERAL CONSTITUTION OF THE SWISSCONFEDERATION

(Adopted1999; last amended 2013)

http://www.admin.ch/ch/e/rs/c101.html

Art. 141 Optional referendum

(1) If within 100 days of the officialpublication of the enactment any50,000 persons eligible to vote or any eight Cantons request it, thefollowing shall be submitted to a vote of the People…

FEDERAL ACT ONPOLITICAL RIGHTS

(Adopted 1976; last amended 2009)

http://www.admin.ch/ch/e/rs/161_1/index.html

Title 4: The Referendum

Chapter 2: The OptionalReferendum

Section 3: Referendumrequested by the Cantons

Art. 67 Competence

Unlesscantonal law provides otherwise, the cantonal parliament shall decide whether a referendum should berequested by a canton.

There area total of 26 cantons.