(Corrects spelling of anniversary in headline)
* FTSEurofirst 300 gains 0.02 percent
* Tech stocks add most points; oil and gas stocks weigh
* Focus on macro data
* For up-to-the-minute market news, click on
By Christoph Steitz
FRANKFURT, Sept 15 (Reuters) - European shares were flat on Tuesday as gains in technology stocks were offset by losses in oil and gas stocks on the day marking the one-year anniversary of the Lehman Brothers collapse.
At 0852 GMT, the FTSEurofirst 300 index of top European shares was up 0.02 percent at 991.04 points after briefly turning negative.
The index has gained 19 percent in 2009, soaring 54 percent since hitting a record-low in March, but is still down about 15 percent from its level in mid-September 2008 before the collapse of Lehman Brothers, once the fourth-largest U.S. investment bank.
"Generally, the recovery has been a bit quick and valuations are no longer attractive but have rather become appropriate," Commerzbank's chief strategist, Hans-Juergen Delp, said.
Technology stocks added the most points to the pan-European index, with Alcatel-Lucent, Infineon and Ericsson up 0.8 to 3.1 percent.
"Still, recent remarks have highlighted that the banking crisis is not over yet," Delp said.
U.S. President Barack Obama warned financial firms on Monday to heed the lessons of Lehman Brothers' collapse on Sept. 15, 2008, adding that signs of an economic recovery were not an excuse to avoid reform.
Oil and gas stocks took most points off the index with BP, Royal Dutch Shell and Tullow Oil down 0.7 to 0.9 percent.
BANKS DOWN, MACRO DATA EYED
Banks also fell, with the DJ STOXX European Banks Index down 0.1 percent, while BNP Paribas, Credit Suisse and HSBC were down between 0.2 and 0.4 percent.
European car stocks were the second-biggest sectoral decliners, down 0.5 percent. BMW, Daimler and Peugeot were all down 0.4 to 1.4 percent amid the Frankfurt Auto Show.
Shares in K+S declined 1.2 percent, as traders pointed to pressure from an interview with CEO Norbert Steiner, saying shortened work hours for employees are likely to continue for K+S workers.
"The comments are basically a reiteration but reinforce the opinion that potash demand will likely stay muted," says a Frankfurt-based trader.
Later in the day, investors will focus on macroeconomic data such as Germany's ZEW economic sentiment due at 0900 GMT and U.S. retail sales PPI at 1230 GMT.
"If positive, as is expected, the data will underline the positive market trend," Commerzbank's Delp said.
Across Europe, Britain's FTSE 100 was 0.01 percent lower, Germany's DAX fell 0.1 percent and France's CAC 40 gained 0.2 percent. (Additional reporting by Tyler Sitte in Frankfurt; Editing by Hans Peters)