Take a look at some of Monday's morning movers:

Berkshire Hathaway - Berkshire leads our list of stocks to watch, following the annual meeting this weekend in Omaha, and Warren Buffett’s live appearance on CNBC’s “Squawk Box” Monday morning from 6 a.m. through 9 a.m. ET.

Tyson Foods - The food producer reported fiscal second-quarter earnings of $0.44 per share, above estimates of $0.39, but sales did come in below consensus. The company sees itself gaining momentum in the second half of the year, and says it still has the potential to earn $2 per share for the year if it executes well.

Procter & Gamble - Wells Fargo has downgraded the stock to "market perform" from "outperform," saying the company's organic sales and market share are lagging that of its competitors. Wells Fargo says P&G lacks upside catalysts until it can demonstrate an ability to expand profit margins.

Vertex Pharmaceuticals - The drugmaker's stock is jumping after its cystic fibrosis combination therapy showed promise in a mid-stage study.

Cognizant Technology - The information technology services company has lowered its full-year earnings forecast. The company says it's seeing a slower-than-anticipated acceleration in demand for its services, echoing what its rivals have seen.

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