What: Shares of engine maker Cummins (NYSE:CMI) plunged 11% in September as a number of analysts lost faith in the company.

So what: Analysts from Deutsche Bank, BB&T Capital Markets, and William Blair all downgraded Cummins stock during September on fears that the company's market share will erode in coming years.

Competition and vertical integration in the heavy-duty truck segment could lead to a market share decline there, and medium-duty trucks could see a decline in market share as well. This is on top of an expected decline in commodities that could weaken demand in some of Cummins' end markets.

Now what: These headwinds aren't new for Cummins, and with the stock trading at 12 times earnings, I think the market has already priced in a lot of the downside risk. One positive is that Cummins has more exposure to the U.S. economic recovery and less exposure to commodities overseas than many industrial competitors. That gives me some hope for growth in the future, and with a 3.6% dividend yield, I see this stock giving investors a lot of value long-term.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.