[Form 4] BIOLIFE SOLUTIONS INC Insider Trading Activity

Rhea-AI Filing Summary

BioLife Solutions (BLFS): Casdin Partners Master Fund reported an open‑market sale of 750,000 shares of common stock on 10/15/2025 at a weighted average price of $28.5471, executed in multiple trades within the $28.50–$28.8354 range. After the transactions, 5,957,165 shares were beneficially owned indirectly. The shares are held directly by the Master Fund and may be deemed to be indirectly beneficially owned by Casdin Capital, Casdin Partners GP, and Eli Casdin.

Insights

Equity Governance Analyst

Large insider sale by a major holder/director; ownership remains significant; neutral on operations, notable for governance signaling.

Casdin Partners Master Fund sold 750,000 shares of **BioLife Solutions (BLFS)** on 10/15/2025 at a weighted average price of $28.5471. Following the sale, 5,957,165 shares are reported as beneficially owned indirectly. The filing lists multiple reporting persons: the Master Fund (direct owner), and indirect beneficial owners Casdin Capital LLC, Casdin Partners GP LLC, and Eli Casdin. The relationship box indicates the reporting person is a Director and a 10% Owner.

This is an ownership change rather than an operational event. It does not alter the company’s capital structure or disclose any change in duties, compensation, or contracts. The transaction was executed as open-market sales with a disclosed price range, and the signatories commit to provide trade-level detail upon request, which supports transparency.

Items to monitor include any subsequent Forms 4 indicating continued selling, changes in beneficial ownership levels relative to 10% thresholds, and any related governance updates. The next relevant signals would be additional ownership filings or board-related disclosures over the coming weeks from 10/2025.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Casdin Partners Master Fund, L.P.

(Last) (First) (Middle)

1350 AVENUE OF THE AMERICAS

SUITE 2600

(Street)

NEW YORK NY 10019

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
BIOLIFE SOLUTIONS INC [ BLFS ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
10/15/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

	Form filed by One Reporting Person
X	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock, par value $0.001 per share	10/15/2025		S		750,000	D	$28.5471(1)	5,957,165	I	Footonote(2)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person^*

Casdin Partners Master Fund, L.P.

(Last) (First) (Middle)

1350 AVENUE OF THE AMERICAS

SUITE 2600

(Street)

NEW YORK NY 10019

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

Casdin Capital, LLC

(Last) (First) (Middle)

1350 AVENUE OF THE AMERICAS

SUITE 2600

(Street)

NEW YORK NY 10019

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

Casdin Partners GP, LLC

(Last) (First) (Middle)

1350 AVENUE OF THE AMERICAS

SUITE 2600

(Street)

NEW YORK NY 10019

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

1. Name and Address of Reporting Person^*

Casdin Eli

(Last) (First) (Middle)

1350 AVENUE OF THE AMERICAS

SUITE 2600

(Street)

NEW YORK NY 10019

(City) (State) (Zip)

Relationship of Reporting Person(s) to Issuer

	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

Explanation of Responses:

1. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions within the range of $28.50 to $28.8354. The Reporting Persons undertake to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

2. The securities are owned directly by Casdin Partners Master Fund, L.P. (the "Master Fund") and may be deemed to be indirectly beneficially owned by (i) Casdin Capital, LLC ("Casdin Capital"), the investment adviser to the Master Fund, (ii) Casdin Partners GP, LLC ("Casdin GP"), the general partner of the Master Fund, and (iii) Eli Casdin, the managing member of Casdin Capital and Casdin GP.

	Casdin Partners Master Fund, LP, By: Casdin Partners GP, LLC,, its General Partner, By: /s/ Eli Casdin, Managing Member	10/17/2025
	Casdin Capital LLC, By: /s/ Eli Casdin, Managing Member	10/17/2025
	Casdin Partners GP LLC, By: /s/ Eli Casdin, Managing Member	10/17/2025
	/s/ Eli Casdin, Eli Casdin	10/17/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What did BLFS insiders report on Form 4?

A sale of 750,000 shares of BioLife Solutions common stock on 10/15/2025 at a weighted average price of $28.5471.

What price range were the BLFS shares sold at?

The trades occurred within a range of $28.50 to $28.8354.

How many BLFS shares were beneficially owned after the sale?

Following the reported transactions, 5,957,165 shares were beneficially owned indirectly.

Who are the reporting persons in this BLFS Form 4?

The securities are owned by Casdin Partners Master Fund, L.P. and may be deemed owned by Casdin Capital, LLC, Casdin Partners GP, LLC, and Eli Casdin.

Was the BLFS transaction a single trade or multiple trades?

It comprised multiple transactions at different prices within the stated range, reflected as a weighted average.

What was the ownership form reported for the BLFS shares?

Ownership was reported as indirect for the post-transaction holdings.