ANNXAnnexon, Inc.

Pharmaceutical Preparations

Revenue: —
Operating margin: —
EBITDA: −$214M; 41% YoY
Market cap: $605M
Employees: 150,000
Net debt / EBITDA: —
AI in 10-K: 0.7; mentions per 10K words

Takeover score 1 of 13

Fixable underperformance 0 of 7

TSR below peersNo
—
3+ of last 5 years
High CEO pay despite TSRNo
$4M median
Median CEO pay ≥ $15M while TSR trails
Earnings not backed by cashNo
—
Cash flow under 80% of net income
Dilutive SBCNo
—
Over 10% of revenue
Payouts exceed cash flowNo
0% of cash flow
Buybacks + dividends over cash flow
Goodwill-heavyNo
—
Over 40% of assets
Shareholder dissentNo
82% lowest support
Any vote under 80% support

Buyer economics 1 of 4

Low revenue per employeeNo
—
Bottom quartile of its SIC industry
Quiet on AINo
0.7 per 10K words · 27th pct
Bottom quartile of AI mentions in 10-Ks
Net cashNo
—
More cash than debt, positive EBITDA
Buyout-sizedYes
$605M market cap
Market cap $500M–$5B

Catalysts 0 of 2

Active 13DNo
0 filings
Active-intent 13D in 18 months
Net insider sellingNo
$12M net
Net sales over $10M in 12 months

Financials

Metric	FY2021	FY2022	FY2023	FY2024	FY2025	YoY	Trend
Operating income	−$131M	−$146M	−$144M	−$154M	−$216M	40%
Net income	−$130M	−$142M	−$134M	−$138M	−$207M	50%
Operating cash flow	−$106M	−$116M	−$121M	−$118M	−$186M	58%
Capex	$2M	$7M	$193K	$15K	$137K	813%
Stock-based comp	$16M	$19M	$18M	$19M	$16M	15%

Deal filings

None.

13D filers

Filed	Filer	Form	Stake	Intent
Nov 21, 2025	Satter Muneer A	SCHEDULE 13D/A	7.2%	Passive
Feb 17, 2023	Satter Muneer A	SC 13D/A	15.0%	Passive
Jul 18, 2022	Satter Muneer A	SC 13D	10.4%	Passive
Aug 27, 2021	Blackstone Holdings II L.P.	SC 13D/A	4.7%	Passive
Aug 7, 2020	Blackstone Holdings II L.P.	SC 13D	7.6%	Passive

Insider trading

Open-market buys, 12 mo: $12M · 13
Open-market sells, 12 mo: $313K · 10
Net: $12M

Pay vs performance

Year	CEO total comp	Comp actually paid	TSR (indexed)	Peer TSR
FY2025	$4M	$5M	20	—
FY2024	$4M	$4M	21	—
FY2023	$2M	$1M	18	—