Feb 13 (Reuters) - President Barack Obamawill meet with chief executive officers on Friday at a summit inSilicon Valley held by the White House that aims to buildsupport for beefing up cybersecurity laws in the wake of massivehacks at Target Corp, Sony Corp and Anthem Inc.

Obama will make the case that the private sector andgovernment need to do more to share data about cyber threats ina speech before a crowd of more than 1,000 people fromcorporations as well as privacy and civil liberties advocates.

"By getting this right, businesses and people around theworld will continue to want to store data with Americancompanies, do business with American retailers, bank withAmerican firms and carry around American smartphones and otherdevices," Jeff Zients, director of the White House NationalEconomic Council, told reporters.

Obama will give a speech at 11:20 a.m. PST (1820 GMT).

He will also meet privately with a small group of businessleaders, part of an effort to mend fences with tech companiesstill angry over damage to their businesses when governmentsurveillance practices were exposed by former National SecurityAgency contractor Edward Snowden.

Upset about the lack of reforms to those practices, the CEOSof Google Inc, Facebook Inc and Yahoo Inc are not attending the Stanford conference. But AppleInc's chief executive, Tim Cook, will give an address.

A long roster of other CEOs will attend, including thosefrom Bank of America, American International Group and Visa.

Obama is set to sign an executive order aimed at encouragingcompanies to share more cyber threat data with the governmentand each other.

And he will urge Congress to pass legislation that wouldoffer liability protection to companies sharing cyber threatdata.

"I think a lot of companies are still uneasy about jumpinginto the debate now," said Michael Gottlieb, a former associateWhite House counsel for Obama.

"Unless more work is done to give a lot of these companiesgreater comfort, they may not be as enthusiastic aboutsupporting those bills, so you may not get the level ofRepublican support that you need as a result," said Gottlieb,who now specializes in data privacy and cybersecurity law atBoies, Schiller & Flexner LLP in Washington, D.C.

On the flip side, privacy and consumer rights advocates wantto make sure companies are held accountable for data breachesthat could have been averted, Gottlieb noted. (Additional reporting by Joseph Menn, Jim Finkle and WarrenStrobel; Writing by Roberta Rampton; Editing by Leslie Adler)