Form
SCHEDULE 13G/A
Passive or exempt beneficial ownership filing.
Adage Capital Management, L.P. - 30 Jun 2025 SCHEDULE 13G/A Report for Cabaletta Bio, Inc. Common Stock, par value $0.00001 per share (CABA)
- Filing manager
- Adage Capital Management, L.P.
- Reporting owner
- Adage Capital Management, L.P.
- Beneficially owned shares
- 9,002,580 shares
- Large-stake signal
-
Ownership
10%Beneficial ownership of this reported class.
Shares
9,002,580 sharesShares beneficially owned as disclosed.
Event date
30 Jun 2025Date tied to the ownership event or amendment.
Accepted by SEC
12 Aug 2025EDGAR acceptance date.
How to read this large-stake filing
- Schedule 13D/G filings focus on beneficial ownership stakes, not a full portfolio.
- Compare this filing with the holder history and issuer page before treating the percentage as a current position.
- Use amendments to understand whether the disclosed stake increased, decreased, or changed reporting status.
- Class ownership
- 10%
- Symbol
- CABA
- Shares outstanding
- 90,115,916 shares
- SEC form
- SCHEDULE 13G/A
- Accepted by SEC
- 12 Aug 2025, 09:04:13 UTC
- Event date
- 30 Jun 2025
- Source filing
- View source filing
Ownership signal
CIK-linked ownership evidence from parsed SEC filings.
2 signals
Subject security
Names, identifiers, and filing context for this profile.
2 source fields
Source evidence
Original filing metadata and source links for verification.
4 source fields
Key filing fact
Adage Capital Management, L.P. disclosed 10% ownership in Cabaletta Bio, Inc. Common Stock, par value $0.00001 per share (CABA) on 30 Jun 2025.
Key facts
- Adage Capital Management, L.P. filed SCHEDULE 13G/A for Cabaletta Bio, Inc. Common Stock, par value $0.00001 per share (CABA).
- Disclosed ownership: 10%.
- Date of event: 30 Jun 2025.
Change
- No earlier schedule filing is available for direct comparison.
- Current filing was accepted on 12 Aug 2025, 09:04.
Research use
- This page turns one Schedule 13D/G filing into a quick large-stake read before the raw reporting-person rows.
- Use the linked SEC filing as the source of truth for ownership percentages, shares, and reporting-party details.
Evidence
Backed by Schedule 13D/13G
View source filing
Beneficial ownership values are sourced from the original SEC Schedule 13D/13G filing.
Reporting persons
Disclosed reporting parties (3)
Names, ownership percentages, voting power, signatures, titles, and CIKs as disclosed in this Schedule 13D/G filing.
| Name | Ownership | Shares owned | Sole voting power | Shared voting power | Signature | Title | CIK |
|---|---|---|---|---|---|---|---|
| Adage Capital Management, L.P. | 10% | 9,002,580 | 0 | 9,002,580 | /s/ Robert Atchinson | By: Adage Capital Partners LLC, its General Partner, By: Robert Atchinson, its Managing Member | |
| Robert Atchinson | 10% | 9,002,580 | 0 | 9,002,580 | /s/ Robert Atchinson | Robert Atchinson, individually | |
| Phillip Gross | 10% | 9,002,580 | 0 | 9,002,580 | /s/ Phillip Gross | Phillip Gross, individually |
CIK / CUSIP context first