SpaceX Tests the IPO Boom: A $123 Billion Lockup Wave Looms

The largest IPO in history is teaching the market a lesson about supply. SpaceX priced 555.6 million shares at $135 on June 11, 2026, raising $75 billion in the offering (with overallotment, the total raised reached roughly $86 billion).^[1] The stock opened at $150, closed its first day at $160.95 — a 19% pop — and pushed the company’s market capitalization above $2 trillion.^[1] Four trading days later it hit an intraday high of $225.64, valuing the company at $2.64 trillion on paper.^[2]

Then the gravity of a 4.2% float set in.^[1]

By Thursday, July 17, SpaceX had closed below its $135 IPO price for the first time, finishing at $131.11 — down 42% from the June 16 peak and declining in eight of nine sessions.^[2] On Friday, July 18, shares fell another 5.4% to $123.99, a sixth consecutive daily decline and a new all-time closing low.^[3] The stock that opened the era of mega-IPOs is now the case study in what happens when the market’s thinnest float meets the first test of insider selling pressure.

The question is no longer whether SpaceX was overvalued at $225 — that has been answered. The question is whether the August lockup cliff is the cathartic event that clears supply and establishes a durable price, or the first crack that closes the IPO window for the AI issuers queued behind it. I put the odds at roughly 60/40 that the lockup expiration is absorbed without breaking the broader issuance cycle — and the 40% scenario is worth understanding in detail.

The Lockup Cliff: 911 Million Shares, Then Maybe 455 Million More

SpaceX engineered an unusual phased lockup structure, departing from the standard 180-day blanket restriction.^[4] According to SEC filings, up to 1.37 billion shares could become eligible to sell starting in the days after the company reports second-quarter results, which FactSet projects for August 6.^[2]

That figure breaks down into two tranches:

• 911.5 million Class A common shares — the base lockup expiration, triggered by the Q2 earnings release.
• 455.8 million additional shares — a conditional tranche that unlocks only if the stock closes at or above $175.50 on a specified number of trading days surrounding the earnings report.^[2]

The scale of the supply shock is what matters. The actual SpaceX IPO sold only 639 million shares.^[2] The first lockup expiration alone could roughly quadruple the tradable supply of SpaceX stock. If the conditional tranche also releases, the float expands by an even larger multiple.

As of the July 18 close at $123.99, the conditional tranche looks unlikely to trigger — the stock would need to rally roughly 41% from current levels to reach the $175.50 threshold in the days around earnings.^[3] That removes the worst-case supply scenario from the table, but it also tells us the market has already repriced SpaceX to a level where the mechanical release valves are narrowing.

The staggered structure SpaceX chose — releasing insider shares in stages rather than all at once on day 180 — was designed to prevent a single-day flood. CNBC reported in May that the company built in “a series of release valves that allow insiders to sell portions of their stock in the weeks and months after the IPO,” a phased approach intended to prevent a concentrated selling event.^[4] Whether that engineering holds under real selling pressure is the August experiment.

The IPO Boom Behind SpaceX: $156 Billion in H1, and Counting

SpaceX is the headline, but it sits atop a broader surge. Through July 2, the US hosted 194 IPOs worth $155.8 billion, according to Dealogic data.^[5] Bloomberg’s tally put first-half US equity issuance at a record $251 billion through June 26, surpassing the prior midyear record set during the 2021 listing frenzy.^[6] Seeking Alpha’s compilation reached $307.7 billion in aggregate proceeds across all equity new issuance.^[6]

Even stripping out SpaceX’s $86.2 billion, the remaining $69.9 billion of IPO paper printed through July 2 was more than double the $31.6 billion raised year-to-date in 2025.^[5] Momentum has continued post-SpaceX: 19 IPOs have priced on US exchanges since the June listing, raising a cumulative ~$6.9 billion, including the $1.68 billion Bending Spoons listing and the $1 billion Doncasters Group (DPC Holdings) IPO.^[5]

UBS forecasts the full-year totals could reach $200–350 billion in IPOs and an additional $400 billion in secondary offerings — both all-time highs.^[7]

Why the Market Can Absorb It (Usually)

The reassuring base rate: UBS notes that combined issuance as a percentage of the $72 trillion US equity market sits in line with long-term historical averages and well below peaks from the 1990s or the financial crisis.^[7] More importantly, corporate buybacks are running at approximately $1.2 trillion annually, meaning corporations will likely retire more stock than they issue this year — net equity supply remains negative.^[7]

UBS also examined the five largest US-domiciled IPOs since 1990 (Visa, General Motors, Meta, AT&T Wireless, Mondelez) and found no discernible impact on broader S&P 500 performance in the weeks surrounding those flotations.^[7] The market is simply too large for a single offering to move the index.

But that analysis addresses the market. It does not address the stock. SpaceX is a localized supply shock within a single name, and the index-inclusion mechanics designed to support its price may not be sufficient to offset a quadrupling of float.

The Index Inclusion Divergence

The three major index providers drew sharply different lines on SpaceX, and the divergence will shape how much mechanical buying flows into the stock — and when.

Bloomberg Intelligence estimates that passive funds tracking the Nasdaq-100 and Russell 1000 will ultimately need to acquire shares equal to approximately 24% of SpaceX’s public float, with a subsequent S&P 500 inclusion (when eligible) adding demand for another 19%.^[1] Goldman Sachs estimates the Nasdaq-100 inclusion alone could trigger as much as $60 billion in forced buying.^[1]

The mechanical buying is funded by proportional selling across every other constituent in the index — index funds run at cash balances below 1% and fund new-name inclusions by trimming existing positions.^[1] When SpaceX enters the Nasdaq-100 at an estimated 0.47%–0.70% initial weight, that same percentage is distributed as selling pressure across the other 100 names.^[1]

The key question is timing. Nasdaq-100 inclusion creates a wave of forced buying, but the lockup expiration creates a wave of optional selling. If the lockup releases hit before or concurrently with the index inflows, the two forces collide. If the index buying arrives first and establishes a floor, the lockup selling may find ready institutional buyers. The sequencing is the variable.

The 40% Scenario: What Would Have to Be True

For the lockup cliff to cascade into a broader IPO-market closure, a specific chain would have to unfold:

1. SpaceX reports disappointing Q2 results on August 6, or the results fail to justify the $1.77 trillion IPO valuation. The company posted 2025 revenue of $18.67 billion against a $4.94 billion GAAP net loss — roughly 100x revenue at the IPO price.^[1] Any disappointment on Starlink subscriber growth, launch revenue cadence, or the AI-infrastructure narrative (Musk’s orbital data-center vision and xAI compute leasing to Anthropic and Alphabet^[5]) would pressure the stock further.

2. The 911 million share lockup release overwhelms index-fund buying. Even with Goldman’s $60 billion Nasdaq-100 inclusion estimate, the market cap of the unlocking shares at current prices is roughly $113 billion (911M × $123.99). The index inflows are front-loaded and mechanical; the insider selling is discretionary and can extend over weeks.

3. The SpaceX selloff triggers a sentiment shift toward AI-issuer valuations. One ECM banker quoted by ION Analytics put it directly: “If SpaceX starts to trade down that could close the door for other AI issuers.”^[5] The same banker noted that investors are already saying they “can’t model these businesses on normal parameters given any ROI will take five-to-10 years to play out.”^[5]

4. Anthropic and OpenAI are forced to delay or reprice. Anthropic confidentially filed its S-1 on June 1, 2026, with a last private valuation of $965 billion following a $65 billion funding round and projected Q2 revenue of $10.9 billion.^[9] OpenAI confidentially filed a week later, on June 8, with a last private valuation of $852 billion following a $122 billion round in March.^[9] Morningstar reported on July 17 that OpenAI executives appear to be hesitating, signaling intent to wait until 2027.^[9] If SpaceX’s lockup selloff deepens, that hesitation could harden into a decision — and Anthropic would face the question of whether to price into a deteriorating tape.

What to Watch Next

• SpaceX Q2 earnings — projected August 6. This is the trigger event. Results, guidance, and management commentary on the AI-infrastructure thesis will determine whether the stock enters the lockup window from a position of strength or weakness. Watch for Starlink revenue, launch cadence, and any commentary on xAI compute-leasing arrangements.

• The 911-million-share lockup release in the days following earnings. Track daily volume relative to the IPO’s average of ~80 million shares.^[1] A sustained spike above 150–200 million shares would signal that insiders are exiting, not just providing liquidity. The staggered structure means the selling pressure should be distributed, but the first release is always the largest test.

• Nasdaq-100 inclusion timing and weight. Nasdaq’s revised fast-entry rule allows top-40 market-cap companies to enter after 15 trading days.^[8] Confirm the effective inclusion date and the initial index weight. Goldman’s $60 billion forced-buying estimate assumes a weight in the 0.47%–0.70% range;^[1] a lower weight at inclusion (given the price decline) would mean less mechanical support.

• Anthropic IPO roadshow timing. Anthropic filed first and is widely expected to price before OpenAI.^[5] If SpaceX stabilizes, the window stays open for a September pricing. If SpaceX continues to slide through August, watch for signals that Anthropic’s bankers are delaying the roadshow or revising the valuation range downward.

• OpenAI’s decision: 2026 or 2027. Morningstar’s July 17 report signals OpenAI is already leaning toward a 2027 listing unless it can command a $1 trillion-plus valuation.^[9] A SpaceX lockup breakdown would likely cement that decision and narrow the window for large AI issuers to one name (Anthropic) this fall rather than two.

• European IPO health as a counter-signal. The EMEA IPO Health Index remains near its post-2021 nadir, with the KNDS IPO postponement the latest failure.^[5] If US issuance begins to slow while Europe remains frozen, it would mark the first synchronized global IPO contraction since 2022.

The base case is that the IPO cycle survives SpaceX’s lockup test — buybacks keep net supply negative, index inclusion provides a structural bid, and the broader market is too large for one stock’s supply shock to matter systemically. The 60% probability I assign to that scenario rests on the assumption that institutional buyers step in once the lockup overhang clears and price discovery settles at a level that reflects the float-expanded reality rather than the 4.2% float scarcity premium.

The 40% scenario — where SpaceX’s slide cascades into delayed AI listings and a narrowing window — requires the lockup selling to be front-loaded and the Q2 earnings to disappoint on the AI-infrastructure narrative that drove the IPO’s valuation. Both are plausible. The next three weeks will tell us which probability is closer to right.