Glossary

Every S-1 term, in plain English.

A reference glossary for reading the SpaceX S-1, the financial press around it, and SpaceX's quarterly earnings releases. Fifty-two terms across IPO mechanics, satellite operations, and finance, alphabetized within each category — updated Nov 4, 2026 with the exercised greenshoe, the staggered lock-up and SpaceX's three reported segments. If we missed one, mail the editor and we'll add it.

IPO Mechanics

Allocation: The number of shares an underwriter gives a specific account (institutional or retail) in an IPO. In oversubscribed deals, retail allocations from broker IPO programs are typically a small fraction of what is requested.
Bookbuilding: The process during the roadshow where underwriters collect indications of demand from institutional investors at various price points. The order book determines the final offer price.
Bookrunner: A senior underwriting bank with primary responsibility for distributing shares and building the order book. SPCX has 23 bookrunners in total; Goldman Sachs is lead-left, Morgan Stanley is stabilization agent. See IPO details.
Class A / Class B shares: A dual-class structure. Class A shares are sold to the public with one vote per share. Class B shares are held by insiders with ten votes per share and convert to Class A when sold. SpaceX uses this structure; Class B retains majority voting power for Musk and insiders. SpaceX reported no Class C shares outstanding at Sept 30, 2026. Full explainer: Class A vs Class B vs Class C shares and which shares have voting rights.
Co-Manager: A junior underwriting role. Co-managers participate in distribution but do not run the books. SPCX has multiple co-managers including HSBC, Mizuho, Nomura, and others.
Effective Date: The date the SEC declares the S-1 registration statement effective, allowing the offering to proceed. Typically the same day as pricing (June 11, 2026 for SPCX).
Free Writing Prospectus FWP: Marketing materials filed with the SEC during the roadshow that supplement the prospectus. These appear on EDGAR.
Greenshoe (Over-Allotment Option): A standard provision giving underwriters the right to sell an additional ~15% of shares within 30 days of pricing if demand is strong; the stabilization agent can also buy shares in the open market to support the price. For SPCX the option covered 83,333,333 additional shares and was exercised, bringing the total sold to 638,888,888 Class A shares — roughly $86 billion gross.
Joint Bookrunner: A bookrunner with shared senior responsibility. Distinct from "lead-left" which is the most senior single bookrunner.
Lead-Left: The most senior bookrunner, named at the upper-left of the S-1 cover page. Lead-left handles the structuring work and tends to keep the senior banking relationship. Goldman Sachs is lead-left on SPCX.
Lock-Up Period: A contractual restriction (typically 180 days) preventing insiders, employees, and pre-IPO investors from selling shares immediately after the IPO. Designed to prevent supply shocks. SPCX's lock-up is staggered rather than a single date: about 911.5 million shares became eligible on Aug 6, 2026, further tranches followed at set day counts and after Q3 results, the standard 180-day period ends in early December 2026 (Dec 8 is the 180th day after pricing), and Musk and other insiders are locked for 366 days, to roughly mid-June 2027. Eligible for sale is not the same as sold. See the SPCX lock-up schedule.
Opening Cross: Nasdaq's auction-based mechanism for setting the first trading price of an IPO. Quote-only period accumulates orders; auction prints a single opening price; continuous trading begins immediately after.
Pricing: The act of finalizing the offer price after the order book closes. SPCX priced on the evening of June 11, 2026 at the fixed $135.00.
Prospectus: The legal disclosure document delivered to investors. The preliminary prospectus is part of the S-1; the final prospectus (424B) is filed at listing.
Roadshow: The marketing campaign run by the underwriters and company management to institutional investors in the 1–2 weeks before pricing. The SPCX roadshow ran the week of June 8, 2026.
S-1: The initial registration statement filed with the SEC for an IPO. Contains business description, risk factors, financial statements, ownership disclosures, and use-of-proceeds language. Filed publicly for SPCX on May 20, 2026.
S-1/A (Amendment): An amendment to the S-1, filed to update terms and address SEC comments. SPCX filed its first S-1/A on June 3, 2026, setting the fixed $135.00 offer price; the final amendment came with the June 11 pricing.
Stabilization Agent: The underwriter responsible for supporting the aftermarket price during the 30-day stabilization window after pricing, using the greenshoe option. Morgan Stanley is stabilization agent for SPCX.
Syndicate: The full group of underwriters participating in the offering — bookrunners and co-managers. SPCX has a 23-bank syndicate.
Underwriter: An investment bank that takes legal and financial responsibility for distributing IPO shares. Earns a fee (the "gross spread") typically 3–7% of the deal — lower on mega-deals.

Satellite & Launch

ARPU Average Revenue Per User: Average monthly or annual revenue generated per subscriber. Critical for connectivity businesses like Starlink. SpaceX now discloses it: Starlink ARPU was $66/month in Q2 2026 (vs $85 a year earlier), and consumer ARPU was $69 in Q3 2026 (vs $83).
Constellation: A coordinated group of satellites in similar orbits working together as one system. Starlink is the largest LEO constellation ever deployed with 9,600+ active satellites.
D2C Direct to Cell: Service from satellites directly to standard LTE/5G mobile handsets without ground modification. Starlink Direct to Cell launched commercially in 2024 with T-Mobile US as anchor partner.
Delta-V dV: A measure of impulse — the change in velocity a rocket can produce. The single most important parameter for orbital mechanics. Often quoted in km/s.
Deorbit: Controlled descent of a satellite back into Earth's atmosphere, burning up on reentry. Required at end-of-life for LEO constellations under modern regulatory standards.
FAA Federal Aviation Administration: The U.S. agency responsible for licensing commercial launches under the Commercial Space Launch Act. Falcon and Starship launches both require FAA approval.
FCC Federal Communications Commission: The U.S. agency responsible for spectrum allocation and licensing satellite communications systems. Starlink operates under FCC authorizations.
GEO Geostationary Orbit: Approximately 36,000 km altitude. Satellites orbit at Earth's rotation rate, appearing stationary in the sky. Used by legacy satellite TV and weather satellites. Higher latency than LEO.
ITU International Telecommunication Union: The UN body that coordinates international spectrum allocation and orbital slot assignments.
LEO Low Earth Orbit: Altitudes from approximately 200 to 2,000 km. Starlink operates at ~340–550 km. Lower latency (~25–50 ms) than GEO; smaller per-satellite coverage requires more satellites.
MEO Medium Earth Orbit: Altitudes between LEO and GEO (typically ~8,000–20,000 km). Used by GPS satellites.
NRO National Reconnaissance Office: The U.S. intelligence agency responsible for designing, operating, and procuring spy satellites. A key Starshield customer.
Payload: The actual customer cargo on a launch — satellite, capsule, or other spacecraft — separate from the rocket itself.
Reusability: Recovering and re-flying rocket stages (Falcon 9 first stage and fairings; Starship both stages). Reduces marginal cost per launch and is the central economic claim of modern SpaceX.
Starbase: SpaceX's launch and development facility in Boca Chica, Texas, where Starship is built and flown.

Finance & Accounting

ASC 280: The U.S. GAAP standard for segment reporting. Governs how SpaceX discloses its three reported segments — Space, Connectivity, and AI (renamed Super Intelligence in Q3 2026). Starshield is not a separately reported segment, and the filings do not break out its revenue.
Capex Capital Expenditure: Spending on long-lived physical assets — satellites, ground stations, launch facilities. Distinct from R&D, which is expensed.
Churn: The rate at which subscribers cancel service. Inverse of retention. Not disclosed for Starlink in the S-1.
Dilution: Reduction in existing shareholders' percentage ownership when new shares are issued. The S-1's "Dilution" section quantifies this for IPO buyers relative to the book value of pre-IPO holders.
Dual-Class Shares: A capital structure with two share classes that have different voting rights. Common in tech IPOs (Meta, Alphabet, Snap). SpaceX uses Class A (1 vote) and Class B (10 votes).
EV / EBITDA: Enterprise Value divided by Earnings Before Interest, Taxes, Depreciation, and Amortization. A common valuation multiple. SpaceX reports adjusted EBITDA, a non-GAAP measure: $6.58 billion for FY2025 and $8.81 billion in Q3 2026 alone.
FCF Free Cash Flow: Operating cash flow minus capex. The cash a business actually generates after maintaining its asset base.
Gross Margin: (Revenue minus Cost of Revenue) divided by Revenue. The economic margin before R&D and SG&A. The Connectivity segment's gross margin is substantially higher than its operating margin.
JOBS Act: U.S. legislation (2012) allowing emerging-growth companies to file S-1s confidentially. SpaceX used JOBS Act confidential filing on April 1, 2026.
MD&A Management's Discussion & Analysis: The narrative section of the S-1 (and quarterly 10-Q / annual 10-K) where management explains the financials. Often the most readable part of a filing.
Operating Margin: Operating Income divided by Revenue. Captures profitability of the core business before interest, taxes, and FX. SPCX consolidated operating margin was ~(14)% in FY2025.
P/E Price / Earnings: Market cap divided by net income. Not meaningful for SPCX on a trailing basis: FY2025 was a ~$4.94 billion net loss and the nine months to Sept 30, 2026 a $(413) million loss, even though Q3 2026 alone earned $4.40 billion.
P/S Price / Sales: Market cap divided by trailing revenue. SPCX priced at ~94× FY2025 revenue at its $1.77T IPO valuation; at the Nov 3, 2026 close (≈$1.9T) it was ≈60× trailing-twelve-month revenue (derived) — see the valuation page.
SBC Stock-Based Compensation: Non-cash compensation paid in shares or options. Material at IPO-ready private companies, often double-digit percent of revenue.
Segment: A business unit a company reports separately under ASC 280, with its own revenue and operating income. SpaceX has three: Space, Connectivity, and Super Intelligence (formerly AI). Products such as Starshield or Starship sit inside the reported structure rather than being segments of their own.
SOTP Sum-of-the-Parts: A valuation method that values each business segment separately and aggregates. Applied to SpaceX's three reported segments in our valuation analysis.
Super Intelligence (SI) segment: The name SpaceX gave its AI segment in the Q3 2026 earnings release. It holds the former xAI business and, since Aug 14, 2026, the acquired Cursor. In Q3 2026 SI was the largest segment by revenue — $7.56 billion, about 52% of the total — with $431 million of operating income after $1.217 billion of acquisition-related stock compensation. SI capex was $16.44 billion of the quarter's $19.59 billion. See the xAI page.