(Updates to midmorning)

By Leah Schnurr

NEW YORK (Reuters) - The S&P 500 briefly pierced akey resistance level Friday, but stocks failed to hold gainsafter data showed consumer sentiment unexpectedly worsened inearly September.

Solid earnings from technology bellwethers Oracle Corp and Research In Motion Ltd limiteddeclines, keeping major indexes little changed in mid-morningtrading.

Consumer sentiment fell to its weakest level in more than ayear, a private survey showed, as worries over jobs andfinances intensified. Earlier, the government said consumerprices increased slightly more than expected in August, butcore prices were flat.

The S&P managed to briefly overcome key technicalresistance around 1,130, pushing through intraday highs set inJune and August. The level has represented the top of a tradingrange for months, and a decisive move above it could be abullish sign.

"Clearly coming into today on a short-term basis we were ina minor uptrend, and the bulls showed they were in command ofthe marketplace in opinion or buying power," said JeffreyFriedman, senior market strategist at Lind-Waldock in Chicago.

If indexes are unable to regain ground before the close oftrading, "it's going to question that concept," said Friedman.

Support for the S&P 500's 200-day moving average remainsaround 1,116, a level it vaulted on Monday.

The Dow Jones industrial average dipped 7.56 points,or 0.07 percent, to 10,587.27. The Standard & Poor's 500 Indexadded 0.17 points, or 0.02 percent, to 1,124.83. TheNasdaq Composite Index rose 4.43 points, or 0.19percent, to 2,307.68.

The quarterly settlement and expiration of four differenttypes of September equity futures and options contracts, alsoknown as "quadruple witching," conclude later Friday, which canadd volatility to the market.

Oracle, the world's No. 3 software maker, and Research InMotion, which makes the BlackBerry smartphone, were the topleaders on the Nasdaq after both posted better-than-expectedresults and gave outlooks that topped expectations.

Oracle shot up 6.4 percent at $26.99, while RIM rose nearly2 percent to $47.29.

Texas Instruments Inc gained 1.8 percent to $25.43after the chipmaker increased its stock repurchase program andboosted its quarterly dividend by 8 percent. (Editing by Jeffrey Benkoe)