By Inyoung Hwang. September 02, 2025 · 5 minute read This content may include information about products, features, and/or services that SoFi does not provide and is intended to be educational in nature. Stock market bubbles occur when speculative trading and investing, fueled by what could be called irrational exuberance, leads to big increases in values for certain assets. Those value increases may not necessarily be supported by much more than market euphoria, and assets can become overvalued.