Rallybio Corp disclosure: Cormorant Asset Management, LP and Bihua Chen report beneficial ownership of 400,000 shares of Rallybio common stock, representing 7.56% of the class. The percentage is calculated using 5,289,675 shares outstanding as of March 6, 2026.
The filing states the shares are held by Cormorant Funds and that Cormorant Global Healthcare Master Fund, LP holds more than 5% of the class. Voting and dispositive power are reported as shared for 400,000 shares; sole power is reported as 0.
Positive
None.
Negative
None.
Insights
Large passive stake disclosed by an investment adviser and affiliated fund.
The statement shows an institutional investor, Cormorant Asset Management, LP, and an associated individual reporting shared voting and dispositive power over 400,000 shares (7.56% of the class as calculated from 5,289,675 shares outstanding as of March 6, 2026).
Such a Schedule 13G-style disclosure typically documents passive or qualifying ownership thresholds for institutional holders; subsequent filings may clarify whether the holdings remain passive or change to active status.
Shared voting/dispositive power suggests control through a fund structure.
The reporting indicates the shares are owned by the Cormorant Funds with voting and dispositive authority shared at 400,000 shares. The filing names Cormorant Global Healthcare Master Fund, LP as an entity holding more than 5%.
Watch for amendments that declare any change in intent or shifts from passive to active ownership, which would alter disclosure status.
Key Figures
Beneficial ownership:400,000 sharesPercent of class:7.56%Shares outstanding:5,289,675 shares+1 more
4 metrics
Beneficial ownership400,000 sharesAmount beneficially owned reported by Cormorant/Bihua Chen
Percent of class7.56%Percent of common stock based on shares outstanding
Shares outstanding5,289,675 sharesShares outstanding used for calculation as of March 6, 2026
CUSIP75120L209Rallybio common stock CUSIP on the filing
Beneficially owned describes securities or assets where a person has the economic rights and control—such as the right to receive dividends and to direct voting—even if legal title is held in another name. Think of it like having the keys and using a car that’s registered to someone else: you get the benefits and make decisions. Investors care because beneficial ownership reveals who truly controls value and voting power, affecting corporate decisions and takeover dynamics.
shared dispositive powerregulatory
"Shared Dispositive Power 400,000.00"
Investment adviser / Cormorant Fundsfinancial
"the investment adviser to certain funds (the "Cormorant Funds")"
Schedule 13G-style joint filingregulatory
"JOINT FILING STATEMENT PURSUANT TO RULE 13d-1(k)"
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
UNDER THE SECURITIES EXCHANGE ACT OF 1934
Rallybio Corp
(Name of Issuer)
Common Stock, par value $0.0001 per share
(Title of Class of Securities)
75120L209
(CUSIP Number)
03/31/2026
(Date of Event Which Requires Filing of this Statement)
Check the appropriate box to designate the rule pursuant to which this Schedule is filed:
Rule 13d-1(b)
Rule 13d-1(c)
Rule 13d-1(d)
schemaVersion:
SCHEDULE 13G
CUSIP Number(s):
75120L209
1
Names of Reporting Persons
Cormorant Asset Management, LP
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
DELAWARE
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
400,000.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
400,000.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
400,000.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
7.56 %
12
Type of Reporting Person (See Instructions)
IA, PN
SCHEDULE 13G
CUSIP Number(s):
75120L209
1
Names of Reporting Persons
Bihua Chen
2
Check the appropriate box if a member of a Group (see instructions)
(a)
(b)
3
Sec Use Only
4
Citizenship or Place of Organization
UNITED STATES
Number of Shares Beneficially Owned by Each Reporting Person With:
5
Sole Voting Power
0.00
6
Shared Voting Power
400,000.00
7
Sole Dispositive Power
0.00
8
Shared Dispositive Power
400,000.00
9
Aggregate Amount Beneficially Owned by Each Reporting Person
400,000.00
10
Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)
11
Percent of class represented by amount in row (9)
7.56 %
12
Type of Reporting Person (See Instructions)
HC, IN
SCHEDULE 13G
Item 1.
(a)
Name of issuer:
Rallybio Corp
(b)
Address of issuer's principal executive offices:
234 CHURCH STREET, NEW HAVEN, CT 06510
Item 2.
(a)
Name of person filing:
Cormorant Asset Management, LP
Bihua Chen
This statement is filed by (i) Cormorant Asset Management, LP, a Delaware limited partnership, and the investment adviser to certain funds (the "Cormorant Funds"), with respect to the shares directly held by the Cormorant Funds and (ii) Bihua Chen with respect to the shares directly held by the Cormorant Funds. The foregoing persons are hereinafter sometimes collectively referred to as the "Reporting Persons." The filing of this statement should not be construed as an admission that any of the foregoing persons or any Reporting Person is, for the purposes of Section 13 of the Act, the beneficial owner of the shares reported herein.
(b)
Address or principal business office or, if none, residence:
200 Clarendon Street, 52nd Floor
Boston, MA 02116
(c)
Citizenship:
Cormorant Asset Management, LP - Delaware
Bihua Chen - United States
(d)
Title of class of securities:
Common Stock, par value $0.0001 per share
(e)
CUSIP Number(s):
75120L209
Item 3.
If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)
Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)
Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)
Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)
Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)
An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)
An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)
A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)
A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)
A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)
A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J),
please specify the type of institution:
(k)
Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.
Ownership
(a)
Amount beneficially owned:
400,000
(b)
Percent of class:
7.56%
(c)
Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote:
0
(ii) Shared power to vote or to direct the vote:
400,000
(iii) Sole power to dispose or to direct the disposition of:
0
(iv) Shared power to dispose or to direct the disposition of:
400,000
The percentages reported herein with respect to the Reporting Persons' holdings are calculated based upon a statement in the Issuer's Annual Report on Form 10-K for the fiscal year ended December 31, 2025, as filed with the Securities and Exchange Commission on March 16, 2026, that there were 5,289,675 shares of Common Stock of the Issuer outstanding as of March 6, 2026.
Item 5.
Ownership of 5 Percent or Less of a Class.
Not Applicable
Item 6.
Ownership of more than 5 Percent on Behalf of Another Person.
If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required.
See Item 2. The Cormorant Funds have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the shares reported herein. Cormorant Global Healthcare Master Fund, LP, a Cormorant Fund, has the right to receive or the power to direct the receipt of dividends or the proceeds from the sale of more than 5% of the shares.
Item 7.
Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
Not Applicable
Item 8.
Identification and Classification of Members of the Group.
Not Applicable
Item 9.
Notice of Dissolution of Group.
Not Applicable
Item 10.
Certifications:
By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11.
SIGNATURE
After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.
Cormorant Asset Management, LP
Signature:
/s/ Bihua Chen
Name/Title:
Bihua Chen, Managing Member
Date:
05/15/2026
Bihua Chen
Signature:
/s/ Bihua Chen
Name/Title:
Bihua Chen
Date:
05/15/2026
Exhibit Information
JOINT FILING STATEMENT
PURSUANT TO RULE 13d-1(k)
The undersigned acknowledge and agree that the foregoing statement on SCHEDULE 13G, is filed on behalf of each of the undersigned and that all subsequent amendments to this statement on SCHEDULE 13G, shall be filed on behalf of each of the undersigned without the necessity of filing additional joint acquisition statements. The undersigned acknowledge that each shall be responsible for the timely filing of such amendments, and for the completeness and accuracy of the information concerning her or it contained therein, but shall not be responsible for the completeness and accuracy of the information concerning the others, except to the extent that she or it knows or has reason to believe that such information is inaccurate.
Dated: May 15, 2026
Cormorant Asset Management, LP
By: Cormorant Asset Management GP, LLC
its General Partner
By: /s/ Bihua Chen
Bihua Chen, Managing Member
Bihua Chen
By: /s/ Bihua Chen
Bihua Chen
What stake does Cormorant Asset Management report in Rallybio (RLYB)?
Cormorant reports beneficial ownership of 400,000 shares, equal to 7.56% of Rallybio's common stock. The percentage is calculated from 5,289,675 shares outstanding as of March 6, 2026, per the filing.
Who specifically holds the reported Rallybio shares for Cormorant?
The shares are held by the Cormorant Funds; the filing identifies Cormorant Global Healthcare Master Fund, LP as having the right to proceeds or dividends for more than 5% of the class.
What voting and dispositive powers are reported for the 400,000 shares?
The filing reports 0 shares with sole voting or dispositive power and 400,000 shares with shared voting and dispositive power, indicating control is exercised jointly within the reporting group.
Does the filing state whether this ownership is passive or active?
The filing is a joint statement by an investment adviser and an individual and reads as a Schedule 13G-style disclosure; it does not include an explicit statement converting the position to active status in the provided excerpt.
