KEN PRIORE
The Lab · kenpriore.ai

Mind the S-1: Anthropic is telling investors its own AI might do things nobody asked it to

Anthropic's S-1 warns that its models may take harmful actions no user directed, and that its safeguards may not always stop people from misusing them. The same document asks the public to buy shares. It goes on to describe a business that depends on scarce chips and power, defends copyright suits, has taken the Department of War to court, and leaves control with a trust and the seven co-founders.

Risk theme · When the model causes harm →
Nasdaq Global Select Market · Class A common stockUpdated for Amendment No. 1, filed
ANT
revenue, nine months to Sep 30, 2026 · p.23$33.2B
cash and short-term investments · p.25$131.8B
customers paying $100K+ a year · p.811,900+
of the vote in one founders' share · p.1350.1%
Fig. 01 · Revenue, $ millions
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The last bar covers nine months only. Log scale shows the rate: about ten times a year.S-1/A, p.23
Revenue rose from $41 million in 2023 to $33.2 billion in the first nine months of 2026
Nine months of 2026 brought in about seven times all of 2025. Costs rose with it. The GAAP operating line is still negative at −$1.3 billion, while the company's adjusted measure shows $4.1 billion of operating income.p.23, 25
13×nine-month revenue against the same period of 2025: $33.2 billion against $2.5 billionp.23
View 02 · The numbers

Where the money goes: compute takes more than half of every dollar spent

Operating costs reached $34.5 billion in the first nine months of 2026, slightly above revenue. Compute and infrastructure took $18.8 billion of it. Sales and marketing grew fastest, from 4% of costs a year earlier to 16%.

Risk theme · Losses, debt and capital · 6,160 words →
Adjusted operating margin
−1,273%2023 · p.25
+12%9M 2026 · p.25
p.25
Fig. 02 · Operating expenses by line
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The Bartz settlement ($1.5B, 2025) is a one-time item. 9M is the nine months to September 30.S-1/A, p.23
Fig. 03 · Operating margin, GAAP and adjusted
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Adjusted margin turns positive in the first nine months of 2026, at +12%, while GAAP is still −4%.S-1/A, p.25
55%of operating costs in the first nine months of 2026 went to compute and infrastructurep.23
16%went to sales, marketing and partnerships, up from 4% in the same period of 2025p.23
$3.3Bstock-based compensation in the first nine months of 2026, inside personnel costsp.23 n.1
View 03 · The loss

A $104.0 billion loss: $94.3 billion of it comes from the notes gaining value

The operating loss in the first nine months of 2026 was $1.3 billion. Most of the rest sits below the operating line: a $94.3 billion non-cash charge for the higher fair value of convertible notes, derivatives and SAFEs, which the filing ties to increases in Anthropic's own valuation, and a new $10.4 billion of other expense, driven mainly by fair-value accounting for its partner financing arrangements.

Risk theme · Losses, debt and capital · 6,160 words →
Share of the nine-month 2026 net loss 91%
came from the fair-value change on convertible notes, derivatives and SAFEs ($94.3B of $104.0B) p.23
Fig. 04 · From revenue to net loss, first nine months of 2026, $ billions
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The yellow bar is the fair-value charge.S-1/A, p.23, 152
The filing's explanation
"Primarily driven by an increase in the fair value of our outstanding convertible promissory notes resulting from an increase in our enterprise valuation."p.23 n.2footnote to the operations table
The balance sheet before conversion
Accumulated deficit at September 30, 2026 was $156.2B against $131.8B of cash and short-term investments. The stockholders' deficit of $149.9B comes before the preferred stock and note conversions at the offering.p.25
View 04 · The compute bet

The compute bet: $313.8 billion committed against $33.2 billion of nine-month revenue

Revenue passed compute spending in the first quarter of 2026. Compute fell to 48% of revenue in the second quarter, then rose to 58% in the third as new capacity arrived, including $5.0 billion of short-term compute the filing says costs significantly more. The fixed commitments run one to twenty years. Three of them are owed "regardless of actual usage".

Risk theme · The compute bet · 9,878 words →
Fixed compute and infrastructure commitments $313.8B of fixed or minimum payments as of September 30, 2026, more than nine times nine-month revenue. Adding short-term commitments, deals signed after September 30 and leases not yet begun, the filing's aggregate is $895.4B. p.F-59, 33, 173–174
Fig. 05 · Quarterly revenue and compute cost, $ millions
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Revenue crossed above compute between Q4 2025 and Q1 2026 (yellow ring).S-1/A, p.160
Fig. 05b · Named compute arrangements, $ billions
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Dashed bars are ceilings ("up to") or, for AMD, the filing's estimate. Terms differ; the bars do not add to the total.S-1/A, p.174–176
+$974MGAAP operating income in Q2 2026, still the only positive quarter in the table. Q3 went back to a $567M loss.p.160
58%of Q3 2026 revenue went to compute and infrastructure, up from 48% in Q2 and down from 251% in Q1 2025p.162
4chip families (AWS Trainium, Google TPUs, NVIDIA and AMD GPUs), run "as a single, fungible pool"p.6, 137
View 05 · Through the clouds

Through the clouds: close to half of revenue reaches Anthropic through cloud marketplaces

Marketplace sales went from 11% of revenue in 2023 to 47% in 2025, and were 44% in the first nine months of 2026. Anthropic counts itself the principal and books those sales gross. The three clouds that sell Claude also sell Anthropic compute, and the filing says they build models of their own.

Risk theme · Customers and sales · 5,398 words →
CSP marketplace sales, first nine months of 2026
44%of revenue · p.58
52%of net accounts receivable at September 30, 2026 · p.58
Fig. 06 · Marketplace share of revenue
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Dollar figures are arithmetic, share times revenue, and the filing gives each share as approximate.S-1/A, p.23, 58
Fig. 07 · Where $100 of marketplace revenue goes
2025 · implied channel fees$15.82–$17.82
9M 2026 · implied channel fees$32.82–$35.02
low endup to the upper-bound estimaterest of the $100
Both ranges are estimates, and the filing discloses no take rate. Fees paid to channel partners rose $341 million in 2025 and $4.8 billion in the first nine months of 2026.S-1/A, p.23, 58, 152, 154
Read these fee ranges with care

The filing says "channel partners", and those aren't only clouds

  • Fees may also go to systems integrators and other partners, and may attach to sales outside the marketplaces. p.3, 147
  • The filing doesn't explain the jump from about $16–$18 to about $33–$35. It does say sales and marketing fell from 22% of revenue in Q1 2026 to 14% in Q3, partly because channel-partner terms changed. p.162
  • The ranges assume all of the increase belongs to marketplace sales, and that prior-period fees fall between zero and all of that period's sales and marketing line. p.23
How the money moves
1

A customer buys

The sale runs through a CSP marketplace. p.58

2

The cloud collects

CSPs act "as collection agents" and "do not obtain control of the Company's intelligence service". p.F-16, F-21

3

Anthropic books it gross

"the Company is the principal and recognizes revenue on a gross basis" p.F-21

4

A fee goes back

Anthropic pays "a fee to each CSP". That fee reads as part of "fees paid to channel partners". p.9, 147

Second sentence inferred

Amazon BedrockAmazon

DistributorOne of three "dedicated AI service layers". Government customers outside the United States and workloads in classified environments can reach Claude here. p.208, 210
SupplierAt least $110.0B of compute, May 2026 to April 2036. p.175
Investor$6.2B of convertible notes outstanding at September 30, 2026, and a $5.0B Series H investment. p.59, F-42
Outside the S-1Amazon's second-quarter release: "Second quarter 2026 net income includes non-operating pre-tax other income of $53.4 billion, primarily from our investments in Anthropic." Amazon Form 8-K, Ex. 99.1, July 30, 2026

Google Cloud PlatformGemini Enterprise Agent Platform

DistributorOne of three "dedicated AI service layers". p.210
SupplierAt least about $121.3B of compute, April 2026 to July 2033, up from $114.5B in the original S-1, plus an estimated $125–$150B of further TPU capacity. p.174–175
InvestorA $10.0B Series H investment, and an option to buy up to $10.0B of Class N at the IPO price. p.171, F-40

Microsoft FoundryMicrosoft

DistributorOne of three "dedicated AI service layers". p.210
SupplierAt least $44.9B of compute, November 2026 to June 2033. p.174
What the filing says about all three

"Amazon, Google, and Microsoft each offer AI services and develop and deploy competing AI models through their respective cloud platforms."

p.75Risk 31
View 06 · Who decides

Who decides: a trust picks the board majority and seven founders hold 50.1% of the vote

Anthropic is a Delaware public benefit corporation, so its directors must weigh a stated Company Purpose alongside returns to stockholders. The Long-Term Benefit Trust elects four of the seven directors. A single Class F share, held through the co-founders' LLC, carries 50.1% of the general vote. Nasdaq will treat Anthropic as a controlled company.

Risk theme · Who controls the company · 4,734 words →
Two levers of control
4 of 7board seats elected by the Long-Term Benefit Trust · p.260
50.1%of the general vote, held by the Founder LLC · p.13
Fig. 08 · Board and vote after the offering
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The LTBT elects four of seven directors through Class T. Class F's 50.1% decides the other three and most stockholder votes.S-1/A, p.12–15, 260
The share classes
CLASS A1 vote · offered to the public CLASS Nno vote · converts to A on sale CLASS TLTBT · elects board majority CLASS Fone share · 50.1% of the vote CLASS Eemployees · limited vote p.15
The public benefit stake
1

5% to a benefit fund

846,840,960 Class N shares to Anthropic Public Benefit Fund, LLC.

2

2% more per 50% rise

Each 50% share-price rise above the prior milestone, from the IPO price, allows up to 2% more.

3

Founders pledge 80%

Each co-founder pledged 80% of personal equity to philanthropy.

4

Employee matching

Employee equity pledged to charity is matched in Class N.

p.12
The Company Purpose
"The responsible development and maintenance of advanced AI for the long-term benefit of humanity." Directors must balance it against stockholders' pecuniary interests and the interests of those materially affected.p.12certificate of incorporation
View 07 · What could go wrong

What could go wrong: compute and policy get the most words in 88 risk factors

Compute leads with 9,878 words, and the longest single factor, at 4,052 words, covers the inputs that compute depends on. Choose any of the ten themes to see its graphic, a summary and the filing's own text.

The risk factors section
88factors
66,033words
94pages, p.27–120
Choose a theme

Also in the filing:

The filing's own caveat
"Many of the risks we face are interconnected and may compound or trigger cascading adverse effects across our business, which could amplify their overall impact."
Risk factor 46, p.87
View 08 · For lawyers

Legal exposure: copyright suits and a case against the Department of War

Yellow marks open matters. Rose marks terms already fixed in the charter, the bylaws and the offering documents.

Risk theme · Training data, copyright and IP · 4,538 words → Modeled · Claude's legal market →
The Bartz settlement $1.5B settles the authors' class action over books used in training. The court approved it in July 2026. The amount equals about a third of 2025 revenue. p.93, F-59
Fig. 09 · Legal and regulatory timeline, Oct 2023 to the amendment
open or adverseresolved or decidedthe filing
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Events evenly spaced, not to scale.S-1/A, p.52, 73, 93, 98, F-59–F-60
Litigation

Most of the open cases are about training data

  • Bartz (authors, books): settled for $1.5B plus interest, approved July 2026. Authors and publishers who opted out have filed their own suits. p.F-59–F-60
  • Concord I (song lyrics): cross-motions for summary judgment heard October 21, 2026. p.F-59
  • Music publishers including Universal, Sony, Warner Chappell, BMG and Round Hill: training and outputs; early stage. p.F-60
  • Reddit: narrowed in September 2026 to contract, interference and unfair competition. p.F-60
  • Canadian actions, including La Presse and an October 2026 claim by Ontario news publishers; consumer class actions over subscription advertising. p.F-59–F-60
  • Antitrust: a September 2026 putative class action claims frontier developers agreed to slow model development, under Sherman Act §1. Risk 59, p.98
Government and national security

An appeals court upheld one supply-chain-risk designation, 2–1

  • Federal agencies were directed to stop using the technology, and the Department of War designated Anthropic a "supply-chain risk" (letters of March 4, 2026). p.73, 245
  • The N.D. Cal. largely granted summary judgment for Anthropic on August 27, 2026. p.73
  • The D.C. Circuit upheld the Section 4713 designation 2–1 on September 25, 2026; rehearing en banc requested. p.73
  • Commerce imposed worldwide export restrictions on Fable 5 and Mythos 5 in June 2026, later lifted. p.73, 100
  • An FTC civil investigative demand in October 2026 covering consumer protection, privacy and product safety. State attorney general inquiries continue. Risk 15, p.52; F-60
IP, data and privacy

The filing calls the law on training "uncertain"

  • How copyright doctrines and open-source licenses apply to model training "are uncertain". Risk 47, p.87
  • Web data collection may create liability or limit use of the data. Risk 51, p.92
  • IP claims "extremely costly to defend" are being defended now. Risk 53, p.93
  • Personal and sensitive data is processed for AI safety work. Risk 49, p.89
  • Security breaches get 2,297 words, the fourth-longest risk factor in the filing. Risk 50, p.89
Corporate governance

A trust elects four of seven directors

  • PBCDirectors balance stockholders, those materially affected and the Company Purpose. p.12
  • LTBTFive trustee seats, one vacant; $400,000 a year each; elects 4 of 7 directors. Christopher Stubbs joined as a trustee in October 2026. p.249–250, 260
  • CLASS FSunset: once fewer than three continuing founders remain for 90 days, a 450-day transition begins. The board then becomes classified. p.251, 260
  • NASDAQControlled company; the exemption is used only for the nominating committee. p.14
Stockholder rights

Class A holders have few ways to challenge the board

  • FORUMDelaware courts for most disputes; federal courts for Securities Act claims. Risk 79, p.113
  • TAKEOVERCharter and bylaws "could make a merger, tender offer, proxy contest… difficult". Risk 80, p.114
  • PBC SUITSBalancing duties may bring "increased litigation". Risk 78, p.112
  • DILUTIONNew Class A and Class N issuances do not dilute Class F voting power. Risk 85, p.118
Offering mechanics

The co-founders are locked up for 365 days

  • ANTNasdaq Global Select; 22 underwriters led by Goldman Sachs and Morgan Stanley. Cover, p.321
  • LOCK-UP180 days for directors, officers and other holders; 365 days for the co-founders and certain holders over 0.5%. p.118–119, 322
  • GOOGLEOption to buy up to $10.0B of Class N at the IPO price, concurrent with the offering. p.171
  • BLANKPrice range, shares offered, proceeds, lock-up percentages. Cover, p.22, 118
Commercial contracts

Minimum spend "regardless of actual usage"

Microsoft at least $44.9B, Google at least about $121.3B and Amazon at least $110.0B. Google and Amazon carry a true-up for shortfalls. p.174–175

Ownership caps on Amazon and Google

Amazon's note conversion is capped at 12% of capitalization (waivable); Google at 14.99%. p.167, 171

A $15B credit facility, and undrawn notes

Up to $77.0B of note capacity from Google, Amazon and Broadcom available at September 30, 2026, with $14.8B of the facility undrawn. p.139, 166

View 09 · Same words

Same words: Amazon in 1997 and Anthropic in 2026

Amazon and Anthropic reach for many of the same words when they talk to investors, 29 years apart.

View 10 · How many people pay for Claude?

How many people pay for Claude? Modeled at 13 to 24 million, and the filing gives no count

The S-1/A reports subscription revenue and customer tiers. It reports no subscriber count. This view works backward from $6,936 million of nine-month subscription revenue, about $771 million a month, using public list prices and three guesses at the mix of plans.

Risk theme · Customers and sales · 5,398 words →
Modeled · not in the filing
13M to 24M paying customers across three cases, with the middle case at 18.3M
What the filing discloses
$6,936Msubscription revenue in the first nine months of 2026, 21% of total revenuep.F-26
~40Mcustomers each under $100,000 of TTM revenue. Here a customer is "a prosumer or an organization that uses our models, platform, or applications."p.2, 144
11,900+at $100K or more
1,900+at $1M or more
~250at $10M or more
distinct organizations by TTM revenue, as of September 30, 2026p.8–9
Modeled · not in the filing · three cases
Fig. 11 · Share of seats and share of revenue by plan, modeled
share of seatsshare of revenue
Fig. 12 · The three cases compared, modeled
seatspaying customers
A Team or Enterprise organization counts as one customer however many seats it holds.
What this rests on
  • The filing gives no seat counts and no split by plan.
  • The prices and mixes in this table are modeling assumptions. Prices sit inside today's public list: Pro $17–$20, Max $100, Ultra $200, Team Standard $20–$25, Team Premium $100–$125, Enterprise $20 a seat plus usage at API rates. They are applied to the first nine months of 2026, when plans and prices may have differed.
  • Treating Enterprise seats this way isn't confirmed by the filing. The model counts the $20 seat fee as subscription revenue and leaves usage out.
  • The model assumes 12 seats per Team organization and 250 per Enterprise organization.
  • Don't subtract these cases from the 40 million. That number is a trailing count of a different group, and these cases come from a nine-month average.
  • The $771 million is a flat average of nine months, and revenue rose fast across them. Q3 alone works out to about $1.24 billion a month (the amendment's nine-month figure less the original S-1's first-half figure), so a current count would run higher. Plans carry usage limits, and token-based use counts as consumption revenue, outside this base. p.F-20, F-26
Modeled · not in the filing
about152,000 US legal users
Direct48,400
Through vendors (less certain)about 104,000
about$84M a year reaching Anthropic from US legal work
Direct$37.5M
Through vendors (less certain)about $46M

This is a model of Claude's use in US legal work, shown at its base case, because Anthropic discloses no legal users, seats or revenue.

See how the legal market model works →
View 12 · Reading guide

The 413 numbered pages: risk factors take 94 of them, more than the business section

Page references are the printed page numbers of Amendment No. 1, filed November 2, 2026, with an F- prefix for the financial statements.

Share of the document23%is risk factors. Financial statements are another 16%.
Fig. 13 · The S-1/A by section, numbered pages
What changed in the amendment
  • Results now run through the nine months ended September 30, 2026. The third quarter shows a GAAP operating loss of $567 million, driven mainly by $5.0 billion of short-term compute. p.23, 138, 162
  • Risk 1 adds that Anthropic may soon meet its Responsible Scaling Policy's definition of "dramatically accelerated progress attributable to AI." Anthropic is also weighing policy updates that would require human review of some research decisions. Risk 1, p.29; p.52
  • New risk text says some compute partners rely on outside financing, so contracted capacity could be delayed, repriced, reduced or not delivered. p.31
  • The aggregate committed spend, blank in the original, is now about $895.4 billion. It covers contractual obligations, short-term commitments, deals signed after September 30 and $451.2 billion of leases not yet begun. Fixed or minimum payments under existing agreements are $313.8 billion. p.33, 173–174; F-59
  • A new section offers some shares to retail investors through brokers including Schwab, Fidelity, Robinhood, SoFi and E*TRADE. p.330
  • Liquidity is now filled in at $146.6 billion. The price range, share counts and proceeds are still blank. p.139; cover, p.18, 125

Figures from Anthropic, PBC's Form S-1 filed with the SEC on October 26, 2026, as updated by Amendment No. 1 filed November 2, 2026, which adds results through September 30, 2026. Page references are the amendment's printed page numbers. Pre-pricing blanks are shown as blank.