CATCo Share News (CAT)

* Oclaro jumps 27 pct as company acquired by Lumentum

* Broadcom gains amid Treasury disapproval of Qualcomm bid

* Dow off 0.48 pct, S&P down 0.05 pct, Nasdaq up 0.46 pct(Updates to late afternoon, changes byline, adds dateline NEWYORK)

By April Joyner

NEW YORK, March 12 (Reuters) - The S&P 500 and the Dow JonesIndustrial Average fell on Monday as worries about the metaltariffs signed into law last week by President Donald Trumpweighed on industrial stocks.

Shares of companies such as Boeing Co, down 2.6percent, and Caterpillar Inc, down 2.3 percent, havebeen under pressure as Trump's protectionist stance on steel andaluminum imports could increase costs and hamper sales abroad.Boeing and Caterpillar were the biggest decliners on the Dow.

Trump last week softened his stance on tariffs by exemptingCanada and Mexico, but negotiations are ongoing as the EuropeanUnion and Japan also seek exemptions.

"The big multinational, industrial companies of the worldare all taking a hit on the concern that they will be thetargets of reprisal sanctions," said Robert Phipps, a directorat Per Stirling Capital Management in Austin.

Those losses were tempered by a CNBC report that LarryKudlow is the leading candidate to replace White House economicadvisor Gary Cohn, Phipps said. Kudlow, like Cohn, is seen bysome investors as a greater proponent of free trade than Trump'sother advisors.

"That offered some comfort to the markets," said Phipps."However, it's not enough of an offset to protect the companiesthat are susceptible to retaliation in a trade war."

The Dow Jones Industrial Average fell 122.02 points,or 0.48 percent, to 25,213.72, the S&P 500 lost 1.39points, or 0.05 percent, to 2,785.18 and the Nasdaq Compositeadded 34.90 points, or 0.46 percent, to 7,595.71.

Even with the session's losses, the S&P 500 is just 3percent below record highs hit on Jan. 26, while the Nasdaqhas recovered its losses from last month's sell-off.

The tech-heavy Nasdaq was lifted in part by further signs ofofficial disapproval of Broadcom Ltd's $117 billion bidfor U.S. graphics chipmaker Qualcomm Inc.

The U.S. Treasury said in a letter to Singapore-basedBroadcom that it had confirmed national security concerns aboutthe bid and that the company had not given sufficient notice ofits plans to redomicile in the United States.

Broadcom gained 3.7 percent while shares in Qualcomm wereflat.

Shares of Micron Technology rose 10.1 percent to$60.09 after analysts at Nomura raised their target for thestock to $100.

Oclaro jumped 28.0 percent after laser and opticalfiber specialist Lumentum Holdings said it would buythe optical components producer for $1.7 billion. Lumentum'sshares rose 5.5 percent.

Advancing issues outnumbered declining ones on the NYSE by a1.18-to-1 ratio; on Nasdaq, a 1.39-to-1 ratio favored advancers.(Additional reporting by Sruthi Shankar in Bengaluru; Editingby Arun Koyyur and Nick Zieminski)