'Scar' still burns for retail investors: Cashin

Though the stock market is soaring to new highs, it's unlikely the retail investor will participate in this market any time soon, veteran trader Art Cashin said Monday on CNBC.

"You had people who got burned at the end of dot-com [bubble], came back, started to feel a little bit better and then had the housing bubble blow up on them," Cashin, director of floor operations at the NYSE for UBS, on "Squawk on the Street." "Yes, we're back at highs. Yes, if they had bought back in or stayed in they might have done equally well, but that scar is still burning, I believe."

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Despite an uneven month and a losing week last week, the major U.S. stock averages are nonetheless on track to post gains for both the month of June and the second quarter. Both the S&P 500 index and Nasdaq will post their sixth straight positive quarters, having not lost ground in a three-month period since the final quarter of 2012. The S&P is positioned for its longest streak of quarterly gains since 1998.

To Cashin, the market rally has been driven by strong quarterly earnings results, as well as corporate buybacks. The former has allowed investors to buy back enough stock to keep the price-to-earnings ratio high, he said.

Looking forward, Cashin said the S&P has to pass the 1,968 to 1,969 level to push higher. It will find resistance at the 1,975 level, he said.

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"So we're very, very close to some testing points that could provide a breakout for the bulls if things get going."

—By CNBC's Drew Sandholm, with CNBC's PeterSchacknow.