Swiss stocks - Factors to watch on May 6

ZURICH May 6 (Reuters) - Swiss stocks were set to open slightly down on Friday after falls on U.S. and Asian markets sparked by disappointing economic data and ahead of key U.S. payrolls data.

The Swiss blue-chip index SMI .SSMI was indicated to fall 5 points to 6,446 points, premarket data provided by bank Clariden Leu showed.CLPRE

The following are some of the main factors expected to affect Swiss stocks on Friday:

NOVARTIS (NOVN.VX)

Novartis AG's cancer drug Afinitor has been approved by the U.S. Food and Drug Administration for a rare type of pancreatic cancer that has few treatment options.

For related news click on [NOVN.VX]

CREDIT SUISSE (CSGN.VX)

Credit Suisse (CSGN.VX) was subpoenaed by the U.S. Securities and Exchange Commission this week for documents related to securitized home loans, according to court documents filed on Thursday by a bond insurer suing Credit Suisse.

For related news click on [CSGN.VX]

UBS (UBSN.VX)

Massachusetts Mutual Life Insurance Co accused four major banks in a lawsuit of hiding the risks on $175.8 million of mortgage-related debt it bought, which lost three-quarters of its value as homeowners defaulted.

For related news click on [UBSN.VX]

TRANSOCEAN (RIGN.VX)

Transocean Ltd (RIGN.VX) (RIG.N), the largest offshore rig operator, sees greater demand for its most capable rigs and those in the midwater class, while the standard deepwater market remains oversupplied.

For related news click on [RIGN.VX]

CLARIANT (CLN.VX)

Swiss specialty chemicals maker Clariant AG (CLN.VX) said demand from emerging markets would drive growth in 2011 as it posted a better-than-expected first quarter profit.

For related news, click on [CLN.VX]

ECONOMY [M-CH]

The Swiss unemployment rate fell to a non-seasonally adjusted 3.1 percent in April from 3.4 percent in the previous month and a forecast in a Reuters poll for 3.3 percent.

When adjusted for seasonal factors, the unemployment rate stood at 3.1 percent after 3.3 percent in the previous month.

COMPANY STATEMENTS [CNR-CH]

* Petroplus PPHN.VX Announces Shareholder Approvals from Its Annual General Meeting [PPHN.VX]

* Sonova (SOON.VX) Increases Turnover by 7.8 percent and Posts New Sales Record in 2010/11 [SOON.VX]

EQUITY RESEARCH [CH-RCH]

FOR COMPANIES TRADING EX-DIVIDEND, PLEASE CLICK ON:

.EX.S for all Swiss stocks

.EXSMI.S for blue chips

.EXNSMI.S for other stocks