Kosacz Barbara

Director at LeonaBio, Inc. · on record since Apr 13, 2026
COO & General Counsel at Kronos Bio, Inc. · on record since Oct 16, 2020
Director at XOMA Royalty Corp · on record since May 26, 2026
Director at eFFECTOR Therapeutics, Inc. · on record since Jan 14, 2021
Director at CERO THERAPEUTICS HOLDINGS, INC. · on record since Oct 12, 2021

Insider trading activity of Kosacz Barbara

Transactions on record: 36; since Jan 3, 2019

Open-market buys: 1; $99.8K

Open-market sells: 1; $12.6K

Companies traded: 5; last filing Jul 14, 2026

Figures computed from official regulatory filings — .

Companies where Kosacz Barbara has traded

XOMA Royalty Corp18 tx · Jul 14, 2026
LeonaBio, Inc.7 tx · Jun 24, 2026
Kronos Bio, Inc.9 tx · $112.3K · Jan 5, 2024
CERO THERAPEUTICS HOLDINGS, INC.1 tx · Oct 12, 2021
eFFECTOR Therapeutics, Inc.1 tx · Jan 14, 2021

Track record of Kosacz Barbara

Insufficient history for a statistical track record (fewer than 5 open-market buys).

Transaction history of Kosacz Barbara

Co-insiders of Kosacz Barbara

This page republishes public regulatory disclosures.

Company	Filed	Type	Qty	Price	Value · USD	Src
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-8,996	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-5,101	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	Other	-6,269	—	n/a (No price was disclosed in the filing)	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-9,763	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-8,167	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-10,967	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-6,152	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-19,979	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
LeonaBio, Inc.Listing unverified	Jun 24, 2026	AwardD (derivative)	28,000	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	May 26, 2026	Award	3,586	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
LeonaBio, Inc.Listing unverified	Apr 13, 2026	AwardD (derivative)	28,000	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
LeonaBio, Inc.Listing unverified	Jun 3, 2025	AwardD (derivative)	20,900	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	May 23, 2025	Award	5,971	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	May 23, 2025	Award	5,971	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
LeonaBio, Inc.Listing unverified	May 24, 2024	AwardD (derivative)	20,900	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	May 17, 2024	AwardD (derivative)	9,763	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
Kronos Bio, Inc.Listing unverified	Jan 5, 2024	Sell	-10,676	1.18 USD	$12.6K	SEC
LeonaBio, Inc.Listing unverified	May 22, 2023	AwardD (derivative)	20,900	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	May 19, 2023	AwardD (derivative)	10,967	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
Kronos Bio, Inc.Listing unverified	Feb 17, 2023	Award	138,911	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
Kronos Bio, Inc.Listing unverified	Feb 17, 2023	AwardD (derivative)	208,367	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
Kronos Bio, Inc.Listing unverified	Jul 27, 2022	Award	53,600	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
LeonaBio, Inc.Listing unverified	May 27, 2022	AwardD (derivative)	13,871	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	May 20, 2022	AwardD (derivative)	8,996	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
Kronos Bio, Inc.Listing unverified	Feb 17, 2022	AwardD (derivative)	80,000	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC

Company	Filed	Type	Qty	Price	Value · USD	Src
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-8,996	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-5,101	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	Other	-6,269	—	n/a (No price was disclosed in the filing)	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-9,763	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-8,167	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-10,967	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-6,152	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	Jul 14, 2026	OtherD (derivative)	-19,979	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
LeonaBio, Inc.Listing unverified	Jun 24, 2026	AwardD (derivative)	28,000	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	May 26, 2026	Award	3,586	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
LeonaBio, Inc.Listing unverified	Apr 13, 2026	AwardD (derivative)	28,000	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
LeonaBio, Inc.Listing unverified	Jun 3, 2025	AwardD (derivative)	20,900	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	May 23, 2025	Award	5,971	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	May 23, 2025	Award	5,971	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
LeonaBio, Inc.Listing unverified	May 24, 2024	AwardD (derivative)	20,900	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	May 17, 2024	AwardD (derivative)	9,763	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
Kronos Bio, Inc.Listing unverified	Jan 5, 2024	Sell	-10,676	1.18 USD	$12.6K	SEC
LeonaBio, Inc.Listing unverified	May 22, 2023	AwardD (derivative)	20,900	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	May 19, 2023	AwardD (derivative)	10,967	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
Kronos Bio, Inc.Listing unverified	Feb 17, 2023	Award	138,911	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
Kronos Bio, Inc.Listing unverified	Feb 17, 2023	AwardD (derivative)	208,367	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
Kronos Bio, Inc.Listing unverified	Jul 27, 2022	Award	53,600	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
LeonaBio, Inc.Listing unverified	May 27, 2022	AwardD (derivative)	13,871	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
XOMA Royalty CorpSecurity delisted	May 20, 2022	AwardD (derivative)	8,996	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC
Kronos Bio, Inc.Listing unverified	Feb 17, 2022	AwardD (derivative)	80,000	0.00 USD	n/a (Non-cash transaction: the filing states a price of zero (award, gift, exercise))	SEC