Even though he tends to be bullish, David Seaburg is starting to get nervous about stocks.
Seaburg, the head of equity sales trading at Cowen, is noticing "a lot of complacency in this tape."
It's not that investors are screamingly bullish, in a way that would be reminiscent of stock market bubbles. To the contrary, Seaburg observes that it looks like a "tired market."
"I really believe that there's not an expectation we go a lot higher in the near term, but there's not a real concern that we're going to fall out of bed, which really scares me," he said Tuesday in a "Trading Nation" segment.
Investors aren't buying protection, either, as evidenced by the 31 percent drop in the CBOE Volatility Index this year. And since investors aren't preparing for much downside, Seaburg frets that a small dip could lead to a major down draft.
"If there is something that sparks a selloff, it could be a lot more exaggerated that people expect," he said.