Bauer, Braun, and Viehs (2010)

Bauer, Rob, Robin Braun, and Michael Viehs. "Industry competition, ownership structure and shareholder activism."  Working paper (Maastricht University), 2010.

From the authors' abstract:  "We study shareholder activism through proxy proposals in the United States from 1997-2006...  By using a distinctive sample that also includes withdrawn and omitted proposals, we circumvent a selection bias towards those proposals that actually go to a vote. We hypothesize that a lack of industry competition in combination with higher managerial entrenchment increases the likelihood of being targeted. Our empirical results support this hypothesis."

Link: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=1633536