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PeoplePublic Stake Value as of Nov 11, 2026

No. 4 by Public Stake Value · AI & tech

Sergey Brin

Google
Public Stake Value
$209.8B
Disclosed US-listed shares × latest close. Not a net worth. As of Nov 11, 2026.
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Latest moves

Sergey BrinPolicyAI & techPrivateAI read · — Bearish for the tax, bullish for Brin

Billionaire tax trails as Brin-backed rival leads

The move

California's Proposition 40, a one-time 5% tax on net worth above $1 billion for state residents as of Jan. 1, 2026, was trailing 55.27% to 44.73% with 61% of votes counted as of a Nov. 4 update, CalMatters reported. A rival measure, Proposition 42, which would bar the state from taxing financial assets or private businesses, was ahead with about 54% support. Under California's rules, when competing measures are on the same ballot, the one with the most votes wins and nullifies the others, so a win for Prop. 42 would void Prop. 40 even if Prop. 40 also passed. Sergey Brin led the opposition, donating $102 million to the committee Building a Better California, which he founded, and relocated his residency out of state.

Why it matters

If the trend holds, California's roughly 200 billionaires avoid a wealth-tax bill that supporters said could raise tens of billions of dollars for healthcare and education.

The bear case

Only 61% of ballots were counted as of the last update, and the union behind Prop. 40 has said it may put the measure back on the ballot in 2028.

What to watch

California's certified final vote count, expected in the coming weeks.

Sergey BrinPolicyOtherPrivateAI read · ▲ Tax fight averted

California's billionaire wealth tax trails after Brin-led opposition

The move

Proposition 40, a one-time 5% tax on the net worth of California's roughly 200 billionaires, trailed 44% to 56% in early returns Wednesday morning, according to the Associated Press. Google co-founder Sergey Brin led the opposition: he moved out of state and donated $102 million to Building a Better California, a committee he founded to fight the measure. Billionaire opponents and business interests spent $316.7 million in total. Two competing measures that would nullify Prop. 40 if either outpolls it were also ahead: Proposition 42, which would ban wealth taxes outright, led with about 55% approval, while Proposition 41 trailed with 52% of voters rejecting it. SEIU-UHW, the union behind Prop. 40, signaled it would try again in 2028.

Why it matters

The result shows how far billionaires are now willing to go, including personally relocating, to stop a wealth-tax experiment, and other states weighing similar measures will be watching whether California's defeat holds once votes are certified.

The bear case

Votes were still being counted Wednesday morning, and California's constitution says either Prop. 41 or Prop. 42 beating Prop. 40 would void it regardless of its own result, so the final outcome isn't locked in yet.

What to watch

California's certified final results on Propositions 40, 41 and 42.

Sergey BrinPolicyOtherPrivateAI read · — Wealth-tax fight

Brin and allies pour $102 million into beating a wealth tax

The move

Sergey Brin has put $102 million into Building a Better California, a campaign group he founded in January, to help defeat Proposition 40, a one-time 5% tax on the net worth of Californians worth more than $1 billion who lived in the state on Jan. 1, 2026. The measure, sponsored by the SEIU-United Healthcare Workers West and backed by Sen. Bernie Sanders and Rep. Ro Khanna, goes to voters on Nov. 3. Through Oct. 20, opponents had spent more than $304 million fighting Prop 40 and backing two counter-measures, Props 41 and 42, which could block the tax even if it passes. Other named contributors include Eric Schmidt, John Doerr, Patrick Collison and Michael Moritz. A Politico analysis found more than 70 current and former California billionaires have directed a record $612 million into state races this cycle.

Why it matters

A yes vote could cost Brin and other ultra-wealthy Californians a one-time payment worth billions combined, and a win for the opposition could become a template for beating similar wealth-tax pushes in other states.

The bear case

Backers say the tax hits only a few thousand people once and could raise tens of billions of dollars for healthcare, and some polling has shown public support for taxing billionaires.

What to watch

The Nov. 3 vote on Propositions 40, 41 and 42.

Larry PageIPO / MarketsAI & techGOOGLAI read · ▼ Earnings miss

Alphabet shares drop 8% despite record revenue

The move

Alphabet, where co-founders Larry Page and Sergey Brin remain large shareholders, reported Q3 revenue of $127.6 billion on Oct. 28, up 25% from a year earlier and just short of the roughly $128 billion analysts expected. Google Cloud revenue roughly doubled to $30.7 billion, up 103%, with its operating margin rising to 36.2% from 23.7%. Net income fell 25% to $26.2 billion, as an $8.7 billion loss on equity investments cut diluted earnings per share to $2.12 from $2.87, well below the nearly $3.00 Wall Street expected. Capital spending rose 114% to $51.4 billion for the quarter, pushing free cash flow to negative $9.1 billion. Shares fell 8.25% in after-hours trading, testing the $300 level.

Why it matters

It's a reminder that heavy AI spending and volatile investment gains can swing Alphabet's bottom line even when its core advertising and cloud businesses are growing fast.

The bear case

Revenue and cloud growth both topped last year's pace, and the earnings miss was driven mainly by a one-time investment loss rather than a change in the underlying business.

What to watch

Whether Alphabet's capex keeps climbing when it reports Q4 results.

Larry PageIPO / MarketsAI & techGOOGLAI read · ▼ Miss despite growth

Alphabet profit misses as cloud revenue doubles

The move

Alphabet reported Q3 2026 revenue of $127.6 billion, up about 25% from a year earlier, with Google Cloud revenue roughly doubling to $30.7 billion. Diluted earnings per share were $2.12, below the $3.01 analysts expected. Shares fell more than 12% the next trading day.

Why it matters

Investors focused on the earnings miss and rising AI infrastructure costs even though cloud growth accelerated sharply.

The bear case

Cloud revenue growth of around 103% suggests the long-term AI buildout is paying off, and one quarter's EPS miss doesn't erase that trend.

What to watch

Alphabet's next earnings report, expected in late January 2027.

Sergey BrinPolicyOtherPrivateAI read · — Big spender

Sergey Brin spends over $100 million fighting California tax

The move

Google co-founder Sergey Brin has put more than $100 million into Building a Better California, a group opposing Proposition 40, the state's proposed one-time 5% tax on billionaires' net worth. Voters decide the measure on Nov 3, 2026.

Why it matters

Brin is one of several wealthy Californians bankrolling the opposition; estimates suggest his own tax bill could run into the billions if it passes.

The bear case

Supporters of the measure, including several Nobel-winning economists, say it would raise billions for the state and argue opponents are overstating the risk of billionaires leaving.

What to watch

Nov 3, 2026: California voters decide Proposition 40.

Larry PageOtherAI & techGOOGLAI read · — Embarrassing outage, not a financial hit

Google Cloud outage knocks out UK banking apps

The move

A Google Cloud outage in its London region (europe-west2) on Oct. 20 disrupted banking apps and other services across the UK and Europe for several hours. Google attributed the disruption to a power event in one zone. Lloyds, Halifax, HSBC and Revolut customers reported being unable to log in or access funds, and court video hearings and delivery services including Royal Mail and DPD were also affected. Google said the issue was mitigated for most customers by the next day, though a small number remained affected.

Why it matters

The outage shows how concentrated some of the UK's banking infrastructure is on a single cloud provider and zone.

The bear case

Google said the root cause was a physical power failure, not a security breach, and most customers recovered within hours.

What to watch

Whether Google publishes a post-incident report naming additional affected customers.

Jensen HuangOtherAI & techPrivateAI read · — Notable

Trump awards top science medals to six tech leaders

The move

At an October 8 "Science: A New Golden Age" summit, President Trump gave the National Medal of Science to Elon Musk, Sergey Brin, Jensen Huang and Lisa Su, and the National Medal of Technology and Innovation to Satya Nadella and Michael Dell. Nvidia separately committed $1 billion over five years to U.S. science at the same event.

Why it matters

It's an unusually direct alignment between the White House and the AI industry's biggest names, following a voluntary accord on AI safety signed earlier.

The bear case

Critics note the honorees' companies have collectively donated billions to Trump-aligned efforts, raising questions about how much the honors reflect scientific merit versus political ties.

What to watch

Any policy follow-through from the summit.

Larry PagePropertyAI & techGOOGLAI read · — Growing pains

Google defends $15B India AI data center amid water fears

The move

Google is building a $15 billion, gigawatt-scale AI data center in Visakhapatnam, India, set to open in 2028 and billed as its biggest AI hub outside the US. Local residents and activists have protested over water supply (local reports put daily supply at about 410 million liters against roughly 480 million liters of demand) and added power demand. Google says it chose air cooling over water cooling in response and has pledged to replenish 120% of the freshwater it uses globally by 2030.

Why it matters

It highlights the tension between the AI buildout's enormous resource needs and pushback from communities hosting the infrastructure.

The bear case

Google's water pledge is a global, aggregate commitment, not a guarantee for Visakhapatnam specifically, and activists want a full moratorium on new data centers in the state pending further study.

What to watch

Whether the project proceeds on its 2028 timeline amid continued local opposition.

Elon MuskRecognitionAI & techTSLA · GOOGL · NVDA · DELLAI read · — Star treatment

Trump gives Musk, Brin, Huang science medals at White House

The move

President Trump awarded the National Medal of Science to Elon Musk, Sergey Brin, Jensen Huang and AMD's Lisa Su at a Washington ceremony on Thursday, October 8. Michael Dell and Microsoft's Satya Nadella received the National Medal of Technology and Innovation instead. Trump called Musk "our modern-day Thomas Edison" and said, "Because of these people here, we will always be on top. No one else can compete with us." Hours before the ceremony, the administration suspended Microsoft and several other companies from the green-card sponsorship program.

Why it matters

The honors double as a message that the administration wants to keep its biggest AI and chip players close, even as it tightens the visa pipeline many of the same companies rely on for talent.

The bear case

A medal ceremony changes nothing about earnings, chip supply or visa policy; it's a photo opportunity timed to distract from the visa suspension announced the same morning.

What to watch

Whether the Permanent Labor Certification suspension affecting Microsoft and Adobe expands to other sponsors.

Larry PagePolicyAI & techGOOGLAI read · ▼ Bearish

Google loses bid to limit $3.2B ad-tech damages claim

The move

A federal judge in New York, Kevin Castel, ruled on Sept. 30 that a class of roughly 5,000 publishers can pursue about $1.7 billion in damages from Google over its AdX ad exchange, with USA Today separately able to seek about $1 billion (before trebling) and Daily Mail General and Trust about $600 million. The judge rejected Google's challenge to the damage calculations and dismissed claims from publishers using different ad-buying tools. The case builds on a 2023 Justice Department lawsuit in which a Virginia judge already found Google illegally monopolized ad-tech markets.

Why it matters

This moves Google's ad-tech liability from a legal theory into dollar figures a jury could actually award, and antitrust lawyers say the ruling increases pressure on Google to settle rather than go to trial.

The bear case

Under U.S. antitrust law, damages can be tripled, so the publishers' claims could realistically be worth far more than the headline $3.2 billion if a jury sides with them.

What to watch

Whether Google moves toward a settlement with the publisher class before a trial date is set.

Source · Insurance JournalRead original ↗Report an error

Recent SEC filings

No SEC filings in the last 90 days.

Form 4 insider trades post within 2 business days. 13F fund holdings can arrive 45 days after quarter end. New to filings? Read Filings 101.

Footprint

Companies

Alphabet Inc. (Google) - Class B sharesGOOGL · Nasdaq · Co-founder, director · 358,939,978 Class B shares =… · as of Dec 2025 · ▲ 2.11%
More
Ticker
GOOGL
Exchange
Nasdaq
Role
Co-founder, director; returned to hands-on AI (Gemini) work in 2023
Stake
358,939,978 Class B shares = 42.86% of Class B (10 votes/share); 5.81% of Class A on as-converted basis (13G/A)
Stake as of
2025-12-31
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Alphabet Inc. - direct holdings per latest Form 4GOOG · Nasdaq · Co-founder, director · 357,921,378 Class B +… · as of Aug 2026 · ▲ 2.08%
More
Ticker
GOOG
Exchange
Nasdaq
Role
Co-founder, director
Stake
357,921,378 Class B + 359,159,912 Class C shares held directly (plus 172,700 each of B and C in two CRUTs)
Stake as of
2026-08-07
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LTA Research & Exploration LLC (rigid airship developer, Pathfinder 1)Founder/backer
More
Role
Founder/backer (founded 2013)
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Stakes

Soneira Bio (psychedelic drug research, via Brin/Catalyst4 ecosystem)
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Tesla (early investor via Bayshore; historical)TSLA · ▲ 3.55%
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23andMe (early investor via Bayshore; historical)
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Investment vehicles

Bayshore Global Management LLCfamily office
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Type
family office
Notes
Brin single-family office founded 2005, Palo Alto HQ; ~$100B AUM (2022 est.); CEO George Pavlov (since 2015), CIO Marie Young (since 2022); Singapore office opened late 2020. No EDGAR filer match found.
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SMB Pacific 2021 Charitable Remainder Unitrusts I and IItrust
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Type
trust
Notes
Each held 172,700 Alphabet Class B shares; Brin sole trustee (13G/A for 12/31/2025).
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MDC Trust Itrust
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Type
trust
Notes
Form 144 (2026-05-12) to sell 409,000 GOOGL Class A shares (~$157.7M) via Morgan Stanley; shares gifted by Brin in 2006.
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Private deals

Terminated or relocated 15 California LLCs in Dec 2025 (seven converted to Nevada entities) ahead of proposed CA…Dec 2025
More
In full
Terminated or relocated 15 California LLCs in Dec 2025 (seven converted to Nevada entities) ahead of proposed CA billionaire tax
Date
2025-12
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Form 144: MDC Trust I proposed sale of 409,000 GOOGL Class A shares (~$157.7M)May 2026
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Form 4: gifted 673,200 Class A (converted from Class B) and 673,200 Class C Alphabet sharesAug 2026
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Form 4: gifted 437,500 Class A and 437,500 Class C Alphabet sharesFeb 2026
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Gift of ~3.5M+ Alphabet shares (~$1.1B) to Catalyst4 (~$1B), Brin family foundation (~$90M), Michael J. Fox Foundation…Nov 2025
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In full
Gift of ~3.5M+ Alphabet shares (~$1.1B) to Catalyst4 (~$1B), Brin family foundation (~$90M), Michael J. Fox Foundation (~$45M); followed ~$700M gift in May 2025
Date
2025-11
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Real estate

Crystal Bay, Lake Tahoe (Nevada side), ~5 acreslakefront estate (now listed primary… · $42M · Dec 2025
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Type
lakefront estate (now listed primary residence)
Price
42000000
Date
2025-12-05
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Malibu, CA (surf-access compound)residential compound · $49.7M · Dec 2025
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Allison Island, Miami Beach, FLwaterfront mansion · $51M · Mar 2026
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Point Dume, Malibu, CAbluff-top mansion · $35M · Jun 2023
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Crystal Bay, Lake Tahoe (Nevada side) - 'Crystal Pointe' estate, ~5 acreslakefront estate (now listed primary… · $42M · Dec 2025
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Type
lakefront estate (now listed primary residence)
Price
42000000
Date
2025-12-05
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Trophies

Pathfinder 1 rigid helium airship (LTA Research), 124.5 m, first flew Oct 2024; flying over SF Bay in 2026
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Superyacht Dragonfly (owned asset)
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Boeing 767-200 and Alpha Jet held jointly with Larry Page (reported)
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Legal & regulatory

US v. Google (search): liability ruling Aug 5, 2024; Sept 2, 2025 remedies barred exclusive contracts and required…
More
In full
US v. Google (search): liability ruling Aug 5, 2024; Sept 2, 2025 remedies barred exclusive contracts and required data sharing but no Chrome/Android divestiture; both sides appealing (2026)
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US v. Google (ad tech): Apr 17, 2025 Judge Brinkema found illegal monopolies in publisher ad server/ad exchange; Sept…
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In full
US v. Google (ad tech): Apr 17, 2025 Judge Brinkema found illegal monopolies in publisher ad server/ad exchange; Sept 2026 remedies imposed behavioral changes but no forced sale of AdX
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California Proposition 40 (one-time 5% billionaire wealth tax) on Nov 2026 ballot; Fortune estimates >$13B potential…
More
In full
California Proposition 40 (one-time 5% billionaire wealth tax) on Nov 2026 ballot; Fortune estimates >$13B potential liability for Brin
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Appointed to President's Council of Advisors on Science and Technology (PCAST), March 2026
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May 2023 crash of Bayshore-owned De Havilland Twin Otter off Half Moon Bay (two fatalities)
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Giving

Sergey Brin Family Foundation (2024 revenue ~$986M)EIN 47-2107200
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Catalyst4 Inc (Palo Alto; founded by Brin 2021)EIN 87-3323607
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Michael J. Fox Foundation / Parkinson's research (>$1B cumulative to Parkinson's)
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Prices via Finnhub · as of Nov 11, 2026 12:24 PM ET. For information only.

What to watch

California Prop 40 billionaire-tax vote; residency/LLC moves to Nevada and Florida may be testedNov 3, 2026
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Appeals in US v. Google search case (DOJ and Google cross-appeals)
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Follow-on to Sept 2026 ad tech remedies ruling (implementation, possible appeals)
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Further Form 144 sales / share gifts by Brin-linked trusts (MDC Trust I, CRUTs)
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Pathfinder 1 airship test flights around SF Bay
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