Some on Wall Street fear the gains have been too exaggerated as the artificial intelligence boom sends semiconductor stocks soaring, and some traders are using leveraged funds to bet a reversal is coming. Shares of artificial intelligence leader Nvidia have risen 41% over the past month, while the Philadelphia Semiconductor Index has risen 17%. Aswath Damodaran, a finance professor at New York University, told CNBC on Thursday that he sold half of his Nvidia stake because its sharp rise made it difficult for value investors to hang on. Some traders are betting more aggressively that the run has gone too far. The Direxion Daily Semiconductor Bear 3x Shares ETF (SOXS) was one of the top 10 exchange-traded funds with the most inflows over the past week, attracting more than $400 million, according to FactSet. The interest comes even though the fund is down about 70% year-to-date. Meanwhile, more than $500 million was withdrawn from Direxion’s Daily Semiconductor Bull 3x Shares ETF (SOXL), the fourth-largest outflow in the past week. FactSet traffic data through Thursday. These funds are often volatile and are not intended for long-term holding, but rather for short-term bets. They also have high expense ratios compared to most other ETFs. “These leveraged ETFs seek returns of 300% or -300% of the benchmark index return in a single day,” Direxion’s website states. “These funds should not be expected to deliver three times or minus three times the benchmark’s cumulative return over a period of more than one day.” As such, their flows can reverse quickly and are not necessarily a good gauge of the long-term outlook for chip stocks. The VanEck Semiconductor ETF (SMH), which is more suitable for long-term investors, saw inflows of just under $40 million this week, a slowdown from previous weeks. Here are the top five ETFs by inflows over the past week. Here are some other notable money flow data points from this week. The Vanguard Tax-Exempt Bond ETF (VTEB) brought in more than $280 million, suggesting MUB’s breakout into the top five could be part of a broader shift toward munis. The iShares Russell 2000 ETF (IWM) saw the most outflows, with more than $785 million in outflows. That largely reversed the previous week’s heavy inflows.