The external influence on media content is a well-known problem and part of the daily business. However, our current findings and statements from the interviews with editors-in-chief show that there is a certain danger in downplaying (or justifying) the influence of external stakeholders. In fact, the question seems to be delicate. The given answers pointed more to (non-)existing external influence but not to (non-) existing company rules.
Interviews with editors and journalists conducted in the course of another research project show that only a few media companies have some basic rule meant to prevent an external influence on media output. One regional newspaper does not allow their editorial staff to be active members of a political party (cf. Meier et al. 2011). Thus, rules are rare.