Julian Emanuel, Wall Street bullion and chief equity and derivatives strategist at BTIG, said that technology stocks, the biggest winners in the US stock market, may already be in a bubble and could trigger adjustments, advising clients to reduce their exposure to technology stocks, CNBC reported on Monday.

According to Emanuel, Facebook Inc, Apple, Amazon, Microsoft and Google are the most vulnerable.

"there is an imbalance, or bubble, in the relative performance between the top and bottom plates. Last year, the technology sector outperformed energy by 78.2%. This is indeed an astonishing number. "

Emanuel also worries that the tech bubble will cause the tech-heavy Nasdaq index to fall by 10%. The Nasdaq index has reached an all-time high 35 times so far this year, and although it closed lower on Monday, it is only 1% from its all-time high.

At the same time, he thinks S & P may struggle to hit new highs and is sure to see a correction given the risk factors in the market looking forward to the election season, but the S & P 500 is not as bubbly as the Nasdaq.

As for what will burst the tech bubble? He thinks it could be an escalation of geopolitical tensions, a US presidential election, or without warning, as it did when the interconnection bubble burst in 2000.

While Emanuel is cautious, he is bullish on the stock outlook for 2021. He expects the economy to fall back because of the coronavirus pandemic and the uncertainty surrounding the presidential election to disappear.