What Is an IPO Lockup Expiration? Why Insider Shares Unlock on a Schedule

An IPO lockup expiration is the date when a contract that barred pre-IPO shareholders from selling after a listing ends, so more of their shares can trade.

When a company goes public, the shares sold in the offering trade freely at once, while most shares held before the listing do not. Founders, employees and early investors usually hold far more (SpaceX sold 638.9 million shares in its IPO, including the underwriters' option, and had about 13.2 billion shares outstanding at 30 June 2026), and a lockup keeps most of those off the market for a period set out in the prospectus. This page covers what a lockup is and who signs it, where its terms are written, why some lockups release shares in tranches rather than all at once, what can and cannot be seen on and after a release date, and a worked example built from SpaceX's prospectus and later filings. It is descriptive throughout.

What a lockup is

A lockup, spelled lock-up in SpaceX's prospectus, is a private contract between the underwriters of an offering and the people who owned the company before it listed. Some holders, often employees, are bound instead by "market standoff" terms in their agreements with the company; SpaceX's prospectus refers to both. The holders agree not to sell, sell short, pledge or hedge their shares without the lead underwriter's consent for a fixed period after the date of the prospectus. In SpaceX's case the company also agreed not to issue new stock for 180 days, with exceptions for employee plans and acquisitions. No SEC rule requires a lockup, though the SEC notes that some states require one under their "blue-sky" laws; terms vary, and the SEC says most prevent insiders from selling for 180 days (see also the IPO explainer).

Because the lockup is a contract with the underwriters, the lead bank can release some or all of it early. SpaceX's prospectus states that Goldman Sachs & Co. LLC, on behalf of the underwriters, "may release any of the securities described above at any time, subject to applicable requirements." When a lead underwriter releases or waives a lockup covering officers and directors, FINRA Rule 5131(d)(2) requires it to notify the company and announce the release or waiver through a major news service at least two business days before it takes effect, unless the release only permits a transfer that is not for consideration, or to an immediate family member, and the transferee agrees in writing to the same lockup terms; the announcement can also come from the company.

A lockup is one of two layers. The other is securities law: shares issued privately before an IPO are "restricted securities" under Rule 144 and can be sold publicly only if they are registered or an exemption applies. Officers, directors and large holders who count as affiliates face extra limits under Rule 144 even after their lockup ends. When selling under Rule 144 rather than under a registration statement, an affiliate can sell in any three months no more than the greater of 1 percent of the shares outstanding or the average weekly trading volume over the previous four calendar weeks, and must file a notice on Form 144 when planned sales in three months exceed 5,000 shares or $50,000. SpaceX's prospectus put its 1 percent figure at approximately 73.8 million shares. Shares sold under an effective registration statement, such as one filed under the registration rights SpaceX's prospectus describes, are not subject to those limits.

Where the terms are written

The terms sit in the registration statement on Form S-1 and in the final prospectus, which appears on EDGAR as a 424B4 filing. Two sections carry them:

• Shares Eligible for Future Sale gives the schedule: each earliest date on which locked shares can be sold and the approximate number of shares freed on it.
• Underwriting, under a "Lock-up Agreements" heading, gives the contract itself: who is bound, what counts as a transfer, the exceptions (gifts, transfers to family trusts, tax withholding on vesting awards) and any early-release triggers.

SpaceX's risk factors repeat the point in a paragraph about future sales by Musk and other existing shareholders. In SpaceX's case the days are counted from the date of the prospectus, 11 June 2026, and the prospectus labels 8 December 2026 as the 180th day. The S-1 explainer covers the rest of the document.

After the listing, other filings add detail. The 10-Q discloses, under Item 408 of Regulation S-K, whether any director or officer adopted or ended a Rule 10b5-1 trading plan during the quarter; a Form S-8 registers shares for employee plans; Form 4 reports an insider's completed trades and Form 144 an affiliate's planned sales.

Why some lockups release in tranches

A simple lockup has a single end date, often day 180, on which every locked share becomes sellable. Lockups can also limit how many shares may be sold over set periods. SpaceX's splits the release into tranches tied to three kinds of trigger:

• Earnings releases. A slice unlocks on the second full trading day after the company publishes quarterly results, which places it after a fresh set of public numbers.
• Calendar dates. Fixed slices unlock on stated days, such as day 70 or day 120.
• Price conditions. An extra slice unlocks early only if the share price has traded far enough above the IPO price for long enough.

Different holders can also sit under different terms. A founder may accept a longer lockup with no early release, a group of large holders may sign an extended lockup, and shares bought through a directed share program for employees and people chosen by management may not be locked at all, as SpaceX's prospectus states for its program, although FINRA Rule 5131(d)(2)(A) requires officers' and directors' lockups to cover any directed shares they buy.

A worked example: the SpaceX (SPCX) lockup schedule

SpaceX sold 555,555,555 Class A shares at $135.00 under a prospectus dated 11 June 2026; with the underwriters' option exercised in full, its 10-Q reports 638.9 million shares sold in the offering. The prospectus sorts the pre-IPO shares into three groups:

• Elon Musk's shares, up to about 6.4 billion including Class B shares and options, locked until the 366th day (12 June 2027) with no early release.
• An extended group, shares several holders agreed to lock until the second full trading day after results for the quarter ending 30 June 2027, with staged releases starting in the first quarter of 2027. Together with the shares Musk owns, this is about 7.8 billion shares, which the prospectus puts at approximately 60 percent of shares outstanding after the offering.
• Everything else, the 180-day group, released in stages through 8 December 2026.

The 180-day group's schedule, from the "Shares Eligible for Future Sale" table:

The price test is written into the underwriting section: the extra 10 percent released only if SpaceX's Nasdaq closing price was at least 30 percent above the $135.00 offering price, so at least $175.50, on at least five of the ten consecutive trading days ending on the date the prospectus calls the First Earnings Release Date, which it ties to the release of second-quarter results. This page does not state whether that test was met; the closing prices for those ten sessions settle it.

The results-linked dates can be placed from EDGAR. SpaceX furnished its second-quarter results on an 8-K accepted by EDGAR at 4:01 pm New York time on Tuesday 4 August 2026, and its third-quarter results on an 8-K accepted at 4:00 pm on Tuesday 20 October 2026. Counting from those releases, the second full trading day was Thursday 6 August for the 20 percent slice and Thursday 22 October for the 28 percent slice. Any release time after the 9:30 am open on those Tuesdays gives the same dates, and both releases scheduled their webcasts for 4:30 pm ET that afternoon. The day-135 date, 24 October 2026, was a Saturday, so the first session after it is Monday 26 October 2026.

The extended group releases up to 351.9 million shares (20 percent) after results for the quarter ending 31 December 2026, further slices on 18 March 2027, after first-quarter 2027 results, on 17 May 2027 and on 12 June 2027, and the rest after results for the quarter ending 30 June 2027. Musk's shares become free after 12 June 2027, a Saturday, so the first session at which they could trade is Monday 14 June 2027.

Every count in the table is "up to" and approximate: the prospectus bases them on shares outstanding at 31 March 2026 and assumes no later option exercises or award settlements.

What is visible on and after an unlock date

A release date moves shares from locked to eligible. Filings and market data show pieces of what happens next, and SpaceX's 2026 filings contain an example of each.

Form 4 for insiders. Officers, directors and holders of more than 10 percent must report trades within two business days (see the Form 4 guide). On 24 September 2026, SpaceX's president and chief operating officer, Gwynne Shotwell, filed a Form 4 showing that on 22 September she exercised options (transaction code M) and sold 342,170 shares (code S) in five lots at weighted average prices from $151.15 to $154.72. The filing says the trades were made under a Rule 10b5-1 plan adopted on 23 June 2026, a plan SpaceX had already disclosed in Item 5 of its second-quarter 10-Q as covering up to 585,605 shares.

Form 144 for affiliates. A Form 144 notice filed on 22 September 2026 covers the same 342,170 shares, with an aggregate market value of $51,958,514.50.

Not every Form 4 is a sale. A Form 4 filed on 15 September 2026 by director Antonio Gracias reported 42,790,223 shares leaving funds affiliated with Valor Equity Partners on 11 September as pro rata distributions in kind to their partners, without payment, under a Rule 10b5-1 distribution plan adopted on 12 June 2026, with transaction code J. An amendment filed on 30 September says the original was filed voluntarily, because the distribution did not change his pecuniary interest. Shares distributed this way reach the funds' partners, who may hold them or, once no lockup covers them, sell them.

Most other holders file nothing individually. Employees, former employees and smaller backers who are not officers, directors or 10 percent owners have no Form 4 duty, so their sales show up only inside ordinary trading volume. Holders of more than 5 percent who are not insiders report on Schedule 13D or 13G instead; Google LLC and Alphabet Inc. filed a Schedule 13G on 14 August 2026 for 7.2 percent of SpaceX's Class A shares.

Volume and short volume. FINRA publishes daily short sale volume for trades reported to its off-exchange facilities; Kresmion's short volume tool carries that file for the symbols it covers, and what is short volume explains why it is a flow measure that includes market makers' intraday activity, not a count of open short positions. For SPCX, around the third-quarter release and the 28 percent slice:

The heaviest off-exchange session that week was the day after the results, one session before the 28 percent slice was free to trade. Because the schedule ties the release to the results, the two events arrive almost together and the volume data cannot separate one from the other. The off-exchange file also leaves out trades executed on exchanges.

What an unlock date does not tell you

A release makes shares eligible for sale; it does not make anyone sell. Holders can keep their shares, sell gradually through a 10b5-1 plan, distribute them to fund investors, or be held back by Rule 144 volume limits if they are affiliates. A larger slice is a larger number of shares that can trade, not a measured amount that did trade. Nothing on this page describes or predicts what a share price does around a release date.

Where Kresmion shows it

Kresmion's SpaceX research page lists the company's recent 10-Q and 8-K filings, the 13F positions of the managers Kresmion tracks and its last daily close. The short volume tool shows a searched symbol's latest session against its own 20-session average, and the insider clusters tool groups Form 4 open-market trades when three or more insiders buy, or three or more sell, the same stock within 30 days. The lockup schedule itself is read from the prospectus on EDGAR. For how the IPO was structured, see the SpaceX IPO explainer, and for the company's segment results, how SpaceX makes money.

Honest limitations

Share counts in a lockup table are maximums, estimated from the share count at a date before the IPO, and the lead underwriter can change the outcome by releasing shares early. Release dates linked to results depend on when the results are published, and this page infers the timing of SpaceX's releases from EDGAR acceptance times rather than from a stated release time. This page does not say whether SpaceX's price-conditioned slice was released. Form 4 covers only officers, directors and 10 percent holders; the off-exchange short volume file covers part of each day's trading, and a short-marked trade is not a short position. The SpaceX figures come from its prospectus dated 11 June 2026, its 10-Qs for the quarters ended 30 June and 30 September 2026, and the Forms 4, 4/A and 144 cited below.

Key takeaways

Frequently asked questions

When does the SpaceX lockup expire?

In stages. Under the prospectus dated 11 June 2026, the 180-day group is fully released on 8 December 2026, after earlier releases on dates including 20 August, 9 and 24 September, 9 and 24 October and the second full trading day after each of the second- and third-quarter results. Elon Musk's shares stay locked until 12 June 2027, and an extended group releases in steps until results for the quarter ending 30 June 2027.

Does a lockup expiration make the stock fall?

This page makes no claim about prices. A release raises the number of shares that may be sold; whether holders sell, and what the price does, are separate questions that filings and volume data describe only after the fact.

Where can I find a company's lockup expiration date?

In its final prospectus on EDGAR, usually filed as a 424B4, under "Shares Eligible for Future Sale" and "Underwriting". The S-1 and its amendments carry the same sections before pricing. Check how the prospectus counts days; SpaceX's counts from the date of the prospectus.

Can a lockup end early?

Yes. The lead underwriter can release or waive it, and some agreements build in early releases tied to earnings dates or the share price. For lockups covering officers and directors, FINRA Rule 5131(d)(2) requires a public announcement at least two business days before a release or waiver takes effect, with an exception for transfers not for value to holders who sign the same lockup.

Do insiders have to report sales after a lockup expires?

Officers, directors and holders of more than 10 percent report each trade on Form 4 within two business days, and affiliates selling under Rule 144 file Form 144 when they place the order for larger sales. Most other pre-IPO holders, such as employees and smaller investors, have no individual reporting duty; holders of more than 5 percent who are not insiders report on Schedule 13D or 13G.

This page is information, not investment advice.

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Source: Space Exploration Technologies Corp., final prospectus (Form 424B4) dated 11 June 2026, filed 12 June 2026, sections "Shares Eligible for Future Sale" and "Underwriting: Lock-up Agreements", https://www.sec.gov/Archives/edgar/data/1181412/000162828026042639/spaceexplorationtechnologi.htm ; Form 10-Q for the quarter ended 30 June 2026, condensed balance sheet and Part II Item 5, https://www.sec.gov/Archives/edgar/data/1181412/000162828026052535/spcx-20260630.htm ; Form 10-Q for the quarter ended 30 September 2026, Note 1, https://www.sec.gov/Archives/edgar/data/1181412/000162828026066880/spcx-20260930.htm ; Forms 8-K furnishing quarterly results on 4 August 2026 and 20 October 2026, with EDGAR acceptance times, https://www.sec.gov/Archives/edgar/data/1181412/000162828026052515/spcx-20260804.htm and https://www.sec.gov/Archives/edgar/data/1181412/000162828026066482/spcx-20261020.htm ; Form 4 of Gwynne Shotwell filed 24 September 2026, accession 0001628280-26-063378 ; Form 144 filed 22 September 2026, accession 0001950047-26-009740 ; Form 4 of Antonio J. Gracias filed 15 September 2026, accession 0001213900-26-100186, and Form 4/A filed 30 September 2026, accession 0001213900-26-105393 ; Rule 144, 17 CFR 230.144, https://www.ecfr.gov/current/title-17/section-230.144 ; Regulation S-K Item 408, 17 CFR 229.408, https://www.ecfr.gov/current/title-17/section-229.408 ; FINRA Rule 5131, https://www.finra.org/rules-guidance/rulebooks/finra-rules/5131 ; FINRA Reg SHO daily short sale volume files for the sessions of 19 to 23 October 2026, https://www.finra.org/finra-data/browse-catalog/short-sale-volume-data , as carried by Kresmion's short volume tool, read 25 October 2026 ; Schedule 13G filed by Google LLC, XXVI Holdings Inc. and Alphabet Inc. on 14 August 2026 (accession 0001193125-26-352289) ; SEC, Initial Public Offerings: Lockup Agreements, https://www.sec.gov/answers/lockup.htm.

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