US STOCKS-Futures flat ahead of data; BP up on 'giant' find

* Private labor market reports on tap

* BP in "giant" oil find in Gulf of Mexico

* Futures: Dow up 1 pt, S&P off 0.5, Nasdaq off 2.75 pts

* For up-to-the-minute market news, click STXNEWS/US

NEW YORK, Sept 2 (Reuters) - U.S. stock index futures were flat on Wednesday ahead of private labor market data, even as BP Plc (BP.L)(BP.N) shares rose after it reported a "giant" oil discovery in the Gulf of Mexico.

* BP rose 4.2 percent to $52.58 in premarket New York trading after the company said it had made a "giant" oil discovery in an area that has assumed increasing importance for Western oil majors. For details, see [ID:nL253648]. The rise also limited losses on the FTSE 100 index .FTSE.

* Challenger, Gray & Christmas will report on private-sector layoff plans at 7:30 a.m EDT (1130 GMT). Also, the ADP jobs report is due at 8:15 a.m. (1215 GMT), with economists polled by Reuters looking for a loss of 250,000 jobs in August versus 371,000 in July.

* "We will be looking at the Challenger cuts and ADP number which tends to be a precursor to the change in the non-farm payroll number at the end of the week," said Art Hogan, chief market analyst at Jefferies & Co in New York.

"British Petroleum has made a discovery in the Gulf of Mexico, and they actually define that as being great, so I think that is going to catch some headlines as we work our way through the day."

* S&P 500 futures SPc1 fell 0.5 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures DJc1 were up 1 point, and Nasdaq 100 futures NDc1 dropped 2.75 points.

* Stocks fell in Europe, but China's key stock index .SSEC closed 1.2 percent higher, led by the banking sector. In Europe the FTSE Eurofirst 300 .FTEU3 fell 0.7 percent.

* The Labor Department will release revised Q2 productivity and unit labor costs at 8:30 a.m. (1230 GMT). Economists forecast a rise of 6.4 percent in productivity and a 5.8 percent fall in unit labor costs, matching data in the previous report.

* The Commerce Department will release July factory orders at 10:00 a.m. (1400 GMT). Economists expect an increase of 2.2 percent, compared with a 0.4 percent rise in June.

* At 2:00 p.m. (1800 GMT), the Federal Open Market Committee issues minutes from its meeting of Aug. 11-12.

* U.S. indexes fell 2 percent on Tuesday on uncertainty over the health of banks. Some investors also fear that a market rally of 50 percent since March has run ahead of economic realities. September is traditionally a weak month for stocks.

(Reporting by Edward Krudy; Editing by Jeffrey Benkoe)