IAA, a digital marketplace for vehicle buyers and sellers, is under pressure from activist investor Ancora Advisors, which is pushing for the ouster of the company's CEO and for the sale of the business.

Why it matters: The activist campaign is a double whammy where the company finds itself forced to defend both its leader and its independence.

• Ancora argues that IAA trades well below its peer, Copart, and could receive a premium offer from a private equity suitor.

Intrigue: It's not clear if Ancora, which has run a number of activist campaigns, is planning to run a slate of directors to take over IAA's board.

• If Ancora decides not to launch a slate, it could proceed with a "vote no" campaign, where investors withhold votes from directors in a sign of no confidence.

What they're saying: The $5.3 billion company said in response to Ancora that it looks forward to continuing its dialogue with the hedge fund and that it will take actions in the best interests of the company and shareholders.