# MFS SERIES TRUST XI

MFS SERIES TRUST XI (CIK 911637) is an SEC-registered fund company with 2 reporting fund series and $17.6B in net assets as of 2026-03-31.

## Registrant

- CIK: 911637
- File number: 811-07992
- LEI: 549300O3TPADV1WWUX67
- Address: 111 HUNTINGTON AVENUE, BOSTON, US-MA, 02199
- Phone: 617-954-5000
- Net assets: $17.6B
- Total assets: $17.6B
- Fund series: 2
- Latest report: 2026-03-31

## Fund series (2)

| Series | Net assets |
| --- | --- |
| [MFS Mid Cap Value Fund](https://search.stillhousedata.com/fund/S000002499) | $16.0B |
| [MFS Blended Research Core Equity Fund](https://search.stillhousedata.com/fund/S000002500) | $1.6B |

## Largest reported holdings (across all series)

| Holding | Value |
| --- | --- |
| [Valero Energy Corp](https://search.stillhousedata.com/security/91913Y100) | $226.6M |
| Flex Ltd | $225.7M |
| [MFS Institutional Money Market Portfolio](https://search.stillhousedata.com/security/55291X109) | $222.5M |
| [PG&E Corp](https://search.stillhousedata.com/security/69331C108) | $200.9M |
| [Permian Resources Corp](https://search.stillhousedata.com/security/71424F105) | $199.2M |
| [Hartford Insurance Group Inc/The](https://search.stillhousedata.com/security/416515104) | $196.5M |
| [Corning Inc](https://search.stillhousedata.com/security/219350105) | $195.3M |
| [Targa Resources Corp](https://search.stillhousedata.com/security/87612G101) | $193.7M |
| [Westinghouse Air Brake Technologies Corp](https://search.stillhousedata.com/security/929740108) | $191.7M |
| [Northern Trust Corp](https://search.stillhousedata.com/security/665859104) | $173.7M |
| [Diamondback Energy Inc](https://search.stillhousedata.com/security/25278X109) | $168.8M |
| [Raymond James Financial Inc](https://search.stillhousedata.com/security/754730109) | $166.5M |
| [CMS Energy Corp](https://search.stillhousedata.com/security/125896100) | $165.9M |
| [L3Harris Technologies Inc](https://search.stillhousedata.com/security/502431109) | $165.3M |
| [US Foods Holding Corp](https://search.stillhousedata.com/security/912008109) | $164.1M |

## More

- [CIK 911637 on SEC EDGAR (source of record)](https://www.sec.gov/cgi-bin/browse-edgar?action=getcompany&CIK=911637&type=&dateb=&owner=include&count=40)
- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/registrant/911637.md)
- [Search all SEC filings, advisers and people on Adviser Search](https://search.stillhousedata.com/)

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Source: public SEC filing data via Adviser Search (https://search.stillhousedata.com).
Agents: this data is also queryable via MCP tools and read-only SQL — see https://search.stillhousedata.com/llms.txt.