A possible surge of mega initial public offerings valued at up to $3 trillion is pushing major index providers to review their inclusion rules, sparking debate over how U.S. equity markets would handle such a large influx of new listings.
According to Goldman Sachs strategists, the ten largest venture-backed private companies in the United States currently carry a combined valuation of about $3 trillion, with “substantial probabilities that several of those companies will go public this year.”
In anticipation of these potential listings, index providers including Nasdaq and FTSE Russell have begun public consultations on potential changes to their eligibility criteria. Proposed adjustments include reducing or eliminating seasoning requirements and lowering minimum free-float thresholds. Reports also suggest S&P Dow Jones Indices is examining similar revisions.
“Each of the three providers has noted the desire to maintain indices that represent – and provide investors with exposure to – the universe of relevant public U.S. equities,” strategists led by Ben Snider said in a note.
If the proposals are adopted, newly listed companies could be added to key indices much sooner than under current rules. Russell may allow IPOs to qualify after only five trading days, while Nasdaq is considering eliminating its existing three-month seasoning requirement and shortening the notice period to less than a month. The S&P 500 currently requires companies to trade publicly for at least 12 months and meet profitability standards before being considered for inclusion.
Despite the scale of the potential IPO pipeline, Goldman believes the overall market impact could be smaller than some investors anticipate. The bank noted that a hypothetical company valued at $1 trillion with only a 5% free float would represent about 0.1% of the S&P 500 and 0.2% of the Russell 1000 Growth index, though it could reach roughly 1.4% in the Nasdaq-100 under the proposed framework.
Strategists added that adding large companies with relatively small public floats “would create less selling pressure on current index constituents than many investors fear.” Passive investment funds tracking major indices would likely generate only limited rebalancing flows, with estimated selling pressure accounting for less than 1% of market capitalization and around 2% of average daily trading volume.
More broadly, Goldman argues that strong corporate demand for equities could help absorb the additional supply. Companies in the S&P 500 repurchased roughly $1 trillion worth of shares in 2025, far exceeding the $298 billion raised through equity issuance, while share buyback authorizations have reached record levels in 2026.
Taken together, Goldman’s strategists believe corporate demand is likely to “easily outweigh supply this year,” even if several large IPOs ultimately come to market.