RLYB

Rallybio Corporation$15.50+0.09 (+0.58%)

Prev Close$15.41·MCap$56.8M·P/E—·Vol43.8K·Yield—

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Buys (12M)

$4.23M

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Sells (12M)

$13.6K

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Net Activity

Net Buyer

$4.22M

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Active Insiders

last 12 mo

Over the past 12 months, insider activity at Rallybio Corporation (RLYB) has been dominated by buying, with 4 insider purchases totaling $4.23M and 2 insider sales totaling $13.6K. The most recent insider transaction was by Lieber Jonathan I (officer: Chief Financial Officer), who sold $9.6K worth of shares on Oct 28, 2026. Rallybio Corporation operates in the Healthcare sector, within the Biotechnology industry, with a market cap of $56.8M.

RLYB Insider Trading Activity

Date	Insider	Role	Type	Shares	Avg Price	Value	Shares After
Oct 28, 2026	Lieber Jonathan I	officer: Chief Financial Officer	Sell	599	$16.04	$9.6K	15,551
May 20, 2026	ADAR1 Capital Management, LLC	10 percent owner	Buy	16,209	$13.98	$226.6K	926,352
May 15, 2026	ADAR1 Capital Management, LLC	10 percent owner	Buy	79,559	$13.99	$1.11M1.5% OS	910,143
May 13, 2026	ADAR1 Capital Management, LLC	10 percent owner	Buy	50,800	$14.00	$711.1K1.0% OS	830,584
May 6, 2026	ADAR1 Capital Management, LLC	10 percent owner	Buy	155,905	$13.97	$2.18M2.9% OS	779,784
Feb 18, 2026	Lieber Jonathan I	Chief Financial Officer	Sell	789	$5.06	$4.0K	0
Mar 16, 2023	Lieber Jonathan I	See Remarks	Buy	5,000	$5.21	$26.1K	5,000
Mar 9, 2023	PARMAR KUSH	Director	Sell	100,000	$8.20	$820.0K1.9% OS	2,378,969
Nov 17, 2022	VIKING GLOBAL INVESTORS LP		Buy	3,333,388	$6.00	$20.00M63.0% OS	3,333,388
Jun 7, 2022	PARMAR KUSH	Director	Sell	150,000	$12.50	$1.88M2.8% OS	2,478,969
May 25, 2022	PARMAR KUSH	Director	Sell	100,000	$13.00	$1.30M1.9% OS	2,578,640
Mar 23, 2022	Fryer Jeffrey M	See Remarks	Buy	3,000	$8.04	$24.1K	47,048
Feb 10, 2022	5AM Opportunities I, L.P.	10% Owner	Sell	210,000	$13.05	$2.74M4.0% OS	2,645,087
Jan 21, 2022	Fryer Jeffrey M	See Remarks	Buy	1,400	$8.70	$12.2K	44,048
Jan 14, 2022	Uden Stephen	See Remarks	Buy	10,000	$9.85	$98.5K	719,127
Jan 12, 2022	MACKAY MARTIN	Chief Executive Officer	Buy	10,000	$10.35	$103.5K	282,609
Jan 11, 2022	Fryer Jeffrey M	See Remarks	Buy	10,000	$9.41	$94.1K	42,648+31%
Aug 4, 2021	Hopfner Robert Lorne	Director	Buy	576,923	$13.00	$7.50M10.9% OS	2,267,411+34%
Aug 4, 2021	HUNT RONALD	Director	Buy	153,846	$13.00	$2.00M2.9% OS	2,147,757
Aug 4, 2021	PARMAR KUSH	Director	Buy	615,384	$13.00	$8.00M11.6% OS	1,406,098+78%
Aug 4, 2021	SHANNON TIMOTHY M	Director	Buy	76,923	$13.00	$1000.0K1.5% OS	2,409,712
Aug 2, 2021	VIKING GLOBAL INVESTORS LP	10% Owner	Buy	806,000	$13.00	$10.48M15.2% OS	4,194,777

RLYB Insider Buying Activity

The following table shows recent insider purchases of Rallybio Corporation (RLYB) stock reported via SEC Form 4 filings.

Date	Insider	Role	Type	Shares	Avg Price	Value	Shares After
May 20, 2026	ADAR1 Capital Management, LLC	10 percent owner	Buy	16,209	$13.98	$226.6K	926,352
May 15, 2026	ADAR1 Capital Management, LLC	10 percent owner	Buy	79,559	$13.99	$1.11M1.5% OS	910,143
May 13, 2026	ADAR1 Capital Management, LLC	10 percent owner	Buy	50,800	$14.00	$711.1K1.0% OS	830,584
May 6, 2026	ADAR1 Capital Management, LLC	10 percent owner	Buy	155,905	$13.97	$2.18M2.9% OS	779,784
Mar 16, 2023	Lieber Jonathan I	See Remarks	Buy	5,000	$5.21	$26.1K	5,000
Nov 17, 2022	VIKING GLOBAL INVESTORS LP		Buy	3,333,388	$6.00	$20.00M63.0% OS	3,333,388
Mar 23, 2022	Fryer Jeffrey M	See Remarks	Buy	3,000	$8.04	$24.1K	47,048
Jan 21, 2022	Fryer Jeffrey M	See Remarks	Buy	1,400	$8.70	$12.2K	44,048
Jan 14, 2022	Uden Stephen	See Remarks	Buy	10,000	$9.85	$98.5K	719,127
Jan 12, 2022	MACKAY MARTIN	Chief Executive Officer	Buy	10,000	$10.35	$103.5K	282,609
Jan 11, 2022	Fryer Jeffrey M	See Remarks	Buy	10,000	$9.41	$94.1K	42,648+31%
Aug 4, 2021	Hopfner Robert Lorne	Director	Buy	576,923	$13.00	$7.50M10.9% OS	2,267,411+34%
Aug 4, 2021	HUNT RONALD	Director	Buy	153,846	$13.00	$2.00M2.9% OS	2,147,757
Aug 4, 2021	PARMAR KUSH	Director	Buy	615,384	$13.00	$8.00M11.6% OS	1,406,098+78%
Aug 4, 2021	SHANNON TIMOTHY M	Director	Buy	76,923	$13.00	$1000.0K1.5% OS	2,409,712
Aug 2, 2021	VIKING GLOBAL INVESTORS LP	10% Owner	Buy	806,000	$13.00	$10.48M15.2% OS	4,194,777

RLYB Insider Selling Activity

The following table shows recent insider sales of Rallybio Corporation (RLYB) stock reported via SEC Form 4 filings.

Date	Insider	Role	Type	Shares	Avg Price	Value	Shares After
Oct 28, 2026	Lieber Jonathan I	officer: Chief Financial Officer	Sell	599	$16.04	$9.6K	15,551
Feb 18, 2026	Lieber Jonathan I	Chief Financial Officer	Sell	789	$5.06	$4.0K	0
Mar 9, 2023	PARMAR KUSH	Director	Sell	100,000	$8.20	$820.0K1.9% OS	2,378,969
Jun 7, 2022	PARMAR KUSH	Director	Sell	150,000	$12.50	$1.88M2.8% OS	2,478,969
May 25, 2022	PARMAR KUSH	Director	Sell	100,000	$13.00	$1.30M1.9% OS	2,578,640
Feb 10, 2022	5AM Opportunities I, L.P.	10% Owner	Sell	210,000	$13.05	$2.74M4.0% OS	2,645,087