Tools/Funds & holdings (13F)

fund.holdings.diff

3 crread-only

Quarter-over-quarter change set for a fund's most recent filing: new positions, adds, reduces, and exits (the signal in 13F).

Parameters#

ParameterTypeDescription
cikreqstringSEC Central Index Key

Example call#

bash
curl -X POST https://arkolith.com/api/mcp \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "fund.holdings.diff",
    "arguments": {
      "cik": "1067983"
    }
  }
}'

Example response#

json
{
  "fund": "BERKSHIRE HATHAWAY INC",
  "cik": "1067983",
  "quarter": "2026-03-31",
  "changes": {
    "new": [{ "issuer": "CONSTELLATION BRANDS", "ticker": "STZ", "value_usd": 1200000000, "pct_delta": null }],
    "added": [{ "issuer": "OCCIDENTAL PETROLEUM", "ticker": "OXY", "value_usd": 13000000000, "pct_delta": 12.4 }],
    "reduced": [{ "issuer": "APPLE INC", "ticker": "AAPL", "value_usd": 75000000000, "pct_delta": -14.29 }],
    "exited": [{ "issuer": "HP INC", "ticker": "HPQ", "value_usd": 0, "pct_delta": -100 }]
  },
  "provenance": { "source": "SEC EDGAR 13F", "license": "public domain" }
}