Longbridge Investors

---
name: longbridge-investors
description: |
  SEC 13F fund-manager–centric view via Longbridge — top-50 active institutional investors by AUM, a specific manager's full portfolio snapshot (by CIK), and quarter-over-quarter holding changes (NEW / ADDED / REDUCED / EXITED). US stocks only. Different from longbridge-flows (stock-centric: who holds a symbol); this skill is manager-centric. Triggers: "基金经理持仓", "机构持仓排名", "大基金持仓", "巴菲特持仓", "贝莱德持仓", "13F基金视角", "基金经理排名", "AUM排名", "季度持仓变化", "基金經理持倉", "機構持倉排名", "大基金持倉", "13F基金視角", "季度持倉變化", "fund manager holdings", "institutional investor", "13F portfolio", "Berkshire holdings", "BlackRock positions", "fund manager ranking", "AUM ranking", "quarterly position changes", "CIK lookup".
license: MIT
metadata:
  author: longbridge
  version: "1.0.0"
  risk_level: read_only
  requires_login: false
  default_install: true
  requires_mcp: false
  tier: read
---

# longbridge-investors

Prompt-only skill. Provides a **fund-manager–centric** view of SEC 13F filings via the Longbridge CLI — who the biggest players are, what a specific manager holds, and how their portfolio changed quarter over quarter.

> **Response language**: match the user's input language — Simplified Chinese / Traditional Chinese / English.

## When to use

- *"全球最大基金经理有哪些"*, *"top institutional investors by AUM"*, *"全球最大基金經理有哪些"*
- *"巴菲特现在持有哪些股票"*, *"Berkshire Hathaway 13F portfolio"*, *"巴菲特現在持有哪些股票"*
- *"贝莱德上季度新建了哪些仓位"*, *"BlackRock new positions last quarter"*, *"貝萊德上季度新建了哪些倉位"*
- *"巴菲特 CIK 是多少"*, *"什么 CIK 是贝莱德"*

For stock-centric institutional-holder queries (*"谁持有 AAPL"* / *"who holds NVDA"*) → route to `longbridge-flows`.

## CLI

Run `longbridge investors --help` to verify exact flags before use. Common calls:

```bash
# Top-50 active fund managers by AUM (includes CIK for each)
longbridge investors --format json

# Full portfolio snapshot for a specific manager
longbridge investors <CIK> --format json
longbridge investors 0001067983 --format json    # Berkshire Hathaway (Buffett)
longbridge investors 0001364742 --format json    # BlackRock

# Limit to top N positions by market value
longbridge investors <CIK> --top 20 --format json

# Quarter-over-quarter holding changes
longbridge investors changes <CIK> --format json
longbridge investors changes 0001067983 --format json

# Help
longbridge investors --help
```

Well-known CIKs (verify via the top-50 list first):

| Manager | CIK |
|---|---|
| Berkshire Hathaway (Buffett) | 0001067983 |
| BlackRock | 0001364742 |

## Workflow

1. **Identify intent**: ranking → run `investors`; portfolio snapshot → run `investors <CIK>`; changes → run `investors changes <CIK>`.
2. **Resolve CIK** if not provided: run `longbridge investors --format json` to get the top-50 list and find the matching manager's CIK.
3. **Fetch data** concurrently where possible.
4. **Present results**:
   - Ranking: table of rank / manager name / AUM / CIK.
   - Portfolio snapshot: table of symbol / shares / market value / % of portfolio; note filing date and reporting period.
   - Changes: group by action (NEW / ADDED / REDUCED / EXITED); show symbol, shares delta, value delta.
5. Cite **Longbridge Securities / SEC 13F**; add disclaimer.

## Output

**Ranking** — *Top-50 institutional investors*

```
Rank | Manager                   | AUM (USD B) | CIK
  1  | BlackRock                 | 10,200      | 0001364742
  2  | Vanguard Group            | 8,400       | 0000102909
  …
```

**Portfolio snapshot** — *Berkshire Hathaway as of {filing date}*

```
Symbol     | Shares (M) | Market Value (USD M) | % Portfolio
AAPL.US    | 905.6      | 174,300              | 47.2%
BAC.US     | 1,032.8    | 35,100               | 9.5%
…
```

**Changes** — *Berkshire Hathaway: Q4 2024 → Q1 2025*

```
NEW:     OXY.US (+18.9M shares, +$1.1B)
ADDED:   AAPL.US (+3.2M, +$620M)
REDUCED: BYD.US (−5.0M, −$280M)
EXITED:  HPQ.US (−7.2M, −$195M)
```

⚠️ 13F 数据滞后约 45 天，仅供参考，不构成投资建议。  
⚠️ 13F 數據滯後約 45 天，僅供參考，不構成投資建議。  
⚠️ 13F filings lag ~45 days. For reference only. Not investment advice.

## Error handling

| Situation | 简体中文回复 | 繁體中文 / English |
|---|---|---|
| `command not found: longbridge` | 回退到 MCP；如也不可用，请安装 longbridge-terminal。 | 回退到 MCP；如也不可用，請安裝 longbridge-terminal。/ Fall back to MCP; if unavailable, install longbridge-terminal. |
| `investors` returns empty | "暂无 13F 数据，CIK 可能有误，请用 `longbridge investors` 列出前50名确认。" | "暫無 13F 數據，請確認 CIK。" / "No 13F data — verify CIK via `longbridge investors`." |
| CIK not found in top-50 | 提示用户运行 `longbridge investors --format json` 获取完整 CIK 列表。 | 提示用戶查看完整 CIK 列表。/ Ask user to run `longbridge investors` for the full CIK list. |
| Other stderr | 直接显示原始错误，不静默重试。 | 顯示原始錯誤。/ Surface verbatim — do not retry silently. |

## MCP fallback

If `longbridge` CLI is unavailable (`command not found`), use MCP tools:

When the CLI is unavailable, fall back to the MCP server. Discover available tools from the MCP server's tool list at runtime — do not rely on hardcoded tool names.

MCP setup: `claude mcp add --transport http longbridge https://openapi.longbridge.com/mcp` (`quote` scope).

## Related skills

- Stock-centric institutional holders → `longbridge-flows`
- Company fundamentals & analyst ratings → `longbridge-fundamental`
- Insider trades (Form 4) → `longbridge-flows`
- Earnings & guidance → `longbridge-earnings`

## File layout

```
longbridge-investors/
└── SKILL.md   # prompt-only, no scripts/
```