Jeremy Hobson: Procter and Gamble — which makes Tide, Spic and Span, and a long list of other household products — is reporting a drop in quarterly sales this morning.

And as our senior business correspondent Bob Moon reports, a big hedge fund could be maneuvering to clean P&G’s house.

Bob Moon: It might be tempting to draw a comparison to circling buzzards, but when an activist investor swoops in over a struggling company, shareholders often see that as a hopeful sign. P&G chief Bob McDonald has been looking vulnerable since his last earnings conference call in April, when analysts like Citigroup’s Wendy Nicholson voiced impatience with the consumer product giant’s withering performance.

Wendy Nicholson: Where is the mea culpa taking responsibility for the weak numbers as opposed to saying, not our fault, it’s just really tough out there?

Since then, activist investor Bill Ackman bought nearly $2 billion worth of P&G shares. It’s a time-tested approach: Find a company that needs fixing, buy an influential stake — and, hopefully, shake things up for the better.

Prof. Charles Elson has watched the rise of activist investors over the past two decades. He heads the University of Delaware’s Center for Corporate Governance.

Charles Elson: They’ve been very successful, not only at creating change in the companies in which they invest, but also creating shareholder value.

Elson views activist investors as beneficial, because they push executives toward more efficient and profitable business practices.

I’m Bob Moon for Marketplace.