Len Blavatnik

CIK 1326628 · last filed 2026-04-20

Len Blavatnik is a corporate insider who has filed 15 SEC Form 4 insider transactions across 6 companies since 2014. The most recent filing, for WMG, was dated Apr 20, 2026. Across all open-market trades the lifetime net is −$2.13B, making them a net seller over the disclosed history. Current disclosed insider exposure totals $1.32B across reported positions.

"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.

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Disclosed Exposure

$1.32B

Companies

6

Total Filings

15

Lifetime Open-Market Net

-$2.13B

Holdings By Company

Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
Symbol Role Shares Price Disclosed Exposure Lifetime OM Net Filings Latest Filed
WMG 10%+ Owner $28.46 $0 1 2026-04-20
IRON 10%+ Owner 3,558,426 $67.99 $241.94M $40.00M 2 2024-06-20
Day One Biopharmaceuticals, Inc. (DAWN) Delisted 11,453,868 $21.53 $246.60M $40.00M 1 2023-06-12
LYB 10%+ Owner 16,766,672 $64.58 $1.08B -$2.21B 8 2022-12-05
Neon Therapeutics, Inc. (NTGN) Delisted 2,752,480 -$2.76M 1 2020-03-25
Loxo Oncology, Inc. (LOXO) Delisted 10%+ Owner 1,368,339 $0 1 2014-08-06

Recent Filings

15 filings
Form 4 transactions across all companies, newest first.
Filed Symbol Action Net Shares Net $ Link
2026-04-20 WMG Other (J) $0 EDGAR
2024-06-20 IRON Grant (A) +1,666,668 $60.00M EDGAR
2023-06-12 Day One Biopharmaceuticals, Inc. (DAWN) Delisted Buy (P) +3,076,920 $40.00M EDGAR
2023-02-17 IRON Buy (P) +1,739,132 $40.00M EDGAR
2022-12-05 LYB Sell (S) −7,141,490 -$606.51M EDGAR
2022-11-18 LYB Sell (S) −135 -$11.7K EDGAR
2021-05-06 LYB Sell (S) −4,635,000 -$501.07M EDGAR
2021-03-09 LYB Other (J) $0 EDGAR
2021-03-03 LYB Mixed −4,876,465 -$503.82M EDGAR
2021-02-24 LYB Sell (S) −1,750,000 -$180.91M EDGAR
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Codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.