Can a section 501(c)(3) organization post information on its website (or link to other websites) about a candidate for public office?
A website is a form of communication. If an organization posts something on its website that favors or opposes a candidate for public office, it is prohibited political campaign activity. Posting information on its website is the same as if the organization distributed printed material or made oral statements or broadcasts that favored or opposed a candidate.
If an organization establishes a link to another website, it is responsible for the consequences of establishing and maintaining that link, even if the organization does not have control over the content of the linked site. Because the linked content may change, the organization should monitor the linked content and adjust or remove any links that could result in prohibited political campaign activity.