The contact information of enrolled students (including their cell phone numbers) is a matter of public record.  This is not ASU policy but a matter of applicable law. 

Under Arizona Public Records Law, ASU’s records are public unless there is a specific confidentiality requirement.  While most student records are confidential under FERPA, FERPA exempts from confidentiality “directory information,” which includes contact information and other basic information like the student’s major, dates of attendance, and enrollment status.  ASU is therefore required to release student directory information upon request.

ASU did not receive a request for its students’ contact information from the campaign at issue. However, it is common for entities that want to advertise to ASU students to request this information  – everything from apartment complexes, to credit cards, to political organizations.  ASU does not control what these entities do with the information they obtain through the public records request process. In addition, the information is available from sources outside the university’s control.

Any student who does not want their directory information to be released may file a form requesting that their information be withheld.   

Also, for more background, here is the ASU Registrar website that explains this, as well as the underlying policy.