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Barbara Kosacz

CIK 1763316 · COO & General Counsel · last filed 2026-07-14

Barbara Kosacz is a COO & General Counsel who has filed 27 SEC Form 4 insider transactions across 8 companies since 2019. The most recent filing, for XOMA, was dated Jul 14, 2026. Across all open-market trades the lifetime net is +$87.1K, making them a net buyer over the disclosed history. Current disclosed insider exposure totals $238.7K 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

$238.7K

Companies

8

Total Filings

27

Lifetime Open-Market Net

$87.1K

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
XOMA Director 0 $40.17 $0 $0 4 2026-07-14
LONA Director — $6.97 — $0 2 2026-06-24
XOMAP Director 9,557 $24.98 $238.7K $0 7 2026-05-26
LeonaBio, Inc. (ATHA) Delisted Director — $6.92 — $0 5 2025-06-03
CERO THERAPEUTICS HOLDINGS, INC. (PBAXW) Delisted Director 5,828 $0.05 $292 $0 1 2024-02-16
Kronos Bio, Inc. (KRON) Delisted COO & General Counsel 928,966 $0.88 $817.5K $87.1K 6 2024-01-05
CERO THERAPEUTICS HOLDINGS, INC. (PBAXU) Delisted Director — $10.37 — $0 1 2021-10-12
LWACU Director — $10.32 — $0 1 2021-01-14

Recent Filings

27 filings
Insider activity across all companies, newest first. Form 4 rows are post-trade confirmations (buys, sells, grants, exercises). Notice (144) rows are pre-trade notices of intent to sell restricted or control stock under Rule 144 — they may not all execute. Compare adjacent dates to see which notices became actual sales.
Filed Symbol Action Net Shares Net $ Link
2026-07-14 XOMA Mixed −6,269 $0 EDGAR
2026-06-24 LONA Grant (A) — $0 EDGAR
2026-05-26 XOMAP Grant (A) +3,586 $0 EDGAR
2026-04-13 LONA Grant (A) — $0 EDGAR
2025-06-03 LeonaBio, Inc. (ATHA) Delisted Grant (A) — $0 EDGAR
2025-05-23 XOMAP Grant (A) +5,971 $0 EDGAR
2025-05-23 XOMAP Grant (A) +5,971 $0 EDGAR
2024-05-24 LeonaBio, Inc. (ATHA) Delisted Grant (A) — $0 EDGAR
2024-05-17 XOMAP Grant (A) — $0 EDGAR
2024-02-16 CERO THERAPEUTICS HOLDINGS, INC. (PBAXW) Delisted Other (J) +5,828 $0 EDGAR
Showing 1–10 of 27
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Form 4 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.
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.