Updated from 9:39 a.m.

Stocks pulled lower on Monday morning as a selloff in health care soured the jobs-inspired rally that pushed benchmark indices to record highs last week.

The S&P 500 was down 0.09%, the Dow Jones Industrial Average fell 0.09%, and the Nasdaq slid 0.25%.

Bristol-Myers Squibb(BMY) - Get Report led the health care sector lower on Monday after Credit Suisse cut its rating to neutral from outperform. The biotech company slumped on Friday in the second-biggest one-day drop in its history after disappointing trial results for a highly anticipated lung cancer treatment. 

Fellow health care stocks moved lower alongside Bristol-Myers. AbbVie(ABBV) - Get Report , Amgen(AMGN) - Get Report , Pfizer(PFE) - Get Report , Merck(MRK) - Get Report and Novartis(NVS) - Get Report were all lower on Monday, while the Health Care Select Sector SPDR ETF (XLV) - Get Report fell 0.9%. 

Stocks secured new records Friday after the latest labor market snapshot breezed past expectations, providing evidence for the U.S. economic recovery. The S&P 500 scored an all-time record close of 2,182.86, while the Nasdaq climbed to a record close of 5,221.12, its first since July last year.

Walmart(WMT) - Get Reportconfirmed a deal to buy online retailerJet.com for roughly $3 billion. Jet.com set out to compete with the likes of Amazon(AMZN) - Get Report by offering deals on home goods such as diapers and cleaning supplies. The deal is the largest ever for an e-commerce company. Walmart said it will maintain Jet's brand.

Mattress Firm (MFRM) rocketed more than 100% higher after Steinhoff International Holdings (SNHFY) agreed to a deal worth $3.8 billion, including debt. Steinhoff offered $64 a share in cash, a deal which both boards unanimously approved. The acquisition represents a 115% premium to Mattress Firm's close on Friday.

Netflix(NFLX) - Get Report slid after Alibaba(BABA) - Get Report dismissed deal rumors. Speculation swirled on Friday that the Chinese e-commerce company could take an investment in the streaming service. 

Delta Airlines(DAL) - Get Report  rebounded from losses on Monday morning after flights began to resume operating as normal after a system-wide computer glitch left thousands of passengers stranded. The glitch had affected flights at airports as wide-ranging as Los Angeles, Tokyo and London.

Sotheby's(BID) - Get Report was on watch after exceeding analysts' estimates in its recent quarter. The auction house earned an adjusted $1.51 a share in its second quarter on revenue of $298.7 million. Analysts anticipated earnings of $1.04 a share on revenue of $282 million.

Tyson Foods(TSN) - Get Report was lower despite a better-than-expected quarter and increased outlook. The owner of Sara Lee earned an adjusted $1.21 a share, above estimates of $1.06. The company also upped its full-year guidance to $4.40 to $4.50 a share, up from previous guidance of $4.20 to $4.30.

Dean Foods(DF) - Get Report slipped after recording another quarter of declining sales, its sixth quarter in a row. Revenue fell 8.2% to $1.85 billion, matching consensus. Lower raw milk costs helped to drive profit higher, though. Adjusted earnings increased to 38 cents a share from 33 cents a share a year earlier. 

Allergan(AGN) - Get Report  moved lower despite earnings coming in higher than expected. The biotech company earned an adjusted $3.35 a share, 2 cents above estimates. Revenue climbed to $3.68 billion but missed estimates of $3.97 billion. Full-year earnings guidance of $13.75 to $14.20 a share met expectations of $14.11.

Allergan is a holding in Jim Cramer's Action Alerts PLUS Charitable Trust Portfolio. Want to be alerted before Cramer buys or sells AGN? Learn more now.

JPMorgan(JPM) - Get Report was downgraded to neutral from buy with a $65 price target, Citi said Monday. Analysts said the move was a valuation call as forward consensus estimates appear too high.

21st Century Fox(FOXA) - Get Report was downgraded to equal weight from overweight at Barclays. The firm removed the stock from its top picks list, citing a lack of near-term catalysts.