Form 4 for HBIO HARVARD BIOSCIENCE INC

Accepted 2026-04-01 09:57:46 ET · period of report 2026-03-20 · accession 0001171843-26-002156 · SEC index · Original document

Summary rows

Aggregated the way they appear in lists: one row per insider, transaction code and security table.

X	Filed	Traded	Ticker	Insider	Title	Type	Price	Qty	Owned	ΔOwn	Value
	2026-04-01 09:57	2026-03-20	HBIO	Frost Mark T	CFO	A - Grant	$0.00	+30.0K	47.5K	+171%	$0

Purchase Sale Sale after option exercise All abbreviations

#	Table	Security	Date	Code	A/D	Shares	Price	Owned after	Own	Exercise / expiry	Underlying	Footnotes
1	Common	Common Stock	2026-03-20	A	A	30,000	$0.00	47,500	D	—	—	(F1) Includes (a) an award granting 30,000 restricted stock units (RSUs) that will vest in three equal installments on March 20, 2027, 2028, and 2029, subject to the terms set forth in an award agreement between the Issuer and the Reporting Person, (b) 5,000 shares of common stock purchased on March 16, 2026, (c) 10,000 RSUs that will vest on May 12, 2026, and (d) 2,500 shares of common stock beneficially owned by the Reporting Person. (F2) On March 13, 2026, the common stock of Harvard Bioscience, Inc. underwent a reverse stock split in a ratio of 10-for-1. The 10,000 RSUs referenced in Footnote 1(c) were previously reported as covering 100,000 RSUs and the 2,500 shares of common stock referenced in Footnote 1(d) were previously reported as covering 25,000 shares of common stock. These numbers have been adjusted to reflect the stock split that occurred on March 13, 2026.