# ImmunoGen, Inc. — DEFA14A

ImmunoGen, Inc. of WALTHAM, MA filed a DEFA14A with the SEC on 2023-11-30. Industry: Pharmaceutical Preparations.

## Filing

- Filed: 2023-11-30
- Form: DEFA14A
- Accession: 0001104659-23-122421
- Registrant: ImmunoGen, Inc.
- CIK: 0000855654
- Industry (SIC): Pharmaceutical Preparations (2834)
- State of incorporation: MA
- Location: WALTHAM, MA

## Documents (4)

| Seq | Type | Description |
| --- | --- | --- |
| 1 | DEFA14A | DEFA14A |
| 2 | EX-2.1 | EXHIBIT 2.1 |
| 3 | EX-99.1 | EXHIBIT 99.1 |
| 4 | GRAPHIC | GRAPHIC |

## Filing timeline for this registrant (60)

_Showing 12 of 60 filings._

| Filed | Form |
| --- | --- |
| [2024-01-29](https://search.stillhousedata.com/proxy/0001104659-24-007789) | DEFA14A |
| [2024-01-24](https://search.stillhousedata.com/proxy/0001104659-24-006288) | DEFA14A |
| [2024-01-08](https://search.stillhousedata.com/proxy/0001104659-24-002244) | DEFA14A |
| [2024-01-02](https://search.stillhousedata.com/proxy/0001104659-24-000347) | DEFM14A |
| [2023-12-21](https://search.stillhousedata.com/proxy/0001104659-23-128277) | PREM14A |
| [2023-12-21](https://search.stillhousedata.com/proxy/0001104659-23-128186) | DEFA14A |
| [2023-11-30](https://search.stillhousedata.com/proxy/0001104659-23-122423) | DEFA14A |
| 2023-11-30 | DEFA14A |
| [2023-04-26](https://search.stillhousedata.com/proxy/0001558370-23-006883) | DEFA14A |
| [2023-04-26](https://search.stillhousedata.com/proxy/0001558370-23-006874) | DEF 14A |
| [2022-04-26](https://search.stillhousedata.com/proxy/0001558370-22-005995) | DEFA14A |
| [2022-04-26](https://search.stillhousedata.com/proxy/0001558370-22-005988) | DEF 14A |

## More

- [CIK 855654 on SEC EDGAR (source of record)](https://www.sec.gov/cgi-bin/browse-edgar?action=getcompany&CIK=855654&type=&dateb=&owner=include&count=40)
- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/proxy/0001104659-23-122421.md)
- [Search all SEC filings, advisers and people on Adviser Search](https://search.stillhousedata.com/)

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