Track activist stakes with Schedule 13D data

Query Schedule 13D filings by percent of class owned, with reporting persons, CUSIPs and the purpose of transaction, as structured JSON.

Anyone who acquires more than 5% of a class of a company's voting equity with an intent to influence control must file Schedule 13D. Passive investors file the shorter 13G. Since December 18, 2024, these schedules must be filed in a structured XML format, which SecFeed parses into flat fields.

Stakes of 10% or more

import os
import requests

BASE = "https://secfeedapi.com"
HEADERS = {"Authorization": f"Bearer {os.environ['SECFEED_KEY']}"}

r = requests.get(f"{BASE}/v1/form-13d-13g",
                 params={"formType": "SCHEDULE 13D", "flat.maxPercentOfClass__gte": 10, "fields": "flat"},
                 headers=HEADERS, timeout=120)
r.raise_for_status()
data = r.json()
print(data["total"], "Schedule 13D filings with a stake of 10% or more")
for f in data["filings"][:8]:
    x = f["flat"]
    names = ", ".join(p["name"] for p in x["reportingPersons"][:2])
    print(f"{f['filedAt']}  {x['issuerName'][:28]:28} {x['maxPercentOfClass']:6.2f}%  {names[:40]}")
first = data["filings"][0]["flat"]
print()
print("Item 4, purpose of transaction:", first["purposeOfTransaction"][:300].replace("\n", " "))

Output:

302 Schedule 13D filings with a stake of 10% or more
2026-10-09  WEBUY GLOBAL LTD              21.69%  Zheng Mingjie
2026-10-09  Omnitek Engineering Corp      85.20%  Hard Rock Holdco LLC, Kevin Jay Hayes, J
2026-10-09  National CineMedia, Inc.      28.90%  Blantyre Capital II Limited
2026-10-09  GOLDENWELL BIOTECH, INC.      20.20%  Ming Zhou
2026-10-09  Nexpu Ltd.                    90.71%  Ruilin Xu
2026-10-08  ESCO Technologies Inc.        16.40%  TBG AG
2026-10-08  5E Advanced Materials, Inc.   12.40%  Karnavati Holdings, Inc., Nirma Limited
2026-10-08  WISeSat.Space Holdings Corp.  88.50%  WISeQey Corp., SEALSQ Corp

Item 4, purpose of transaction: The information contained in Item 2(c) of this Schedule 13D is incorporated herein by reference.  The Reporting Person acquired beneficial ownership of the securities reported herein in connection with the PIPE.  The Reporting Person acquired the securities reported herein for investment purposes. T

Flat fields

Item 4 is the interesting part

purposeOfTransaction is where the filer explains its plans: seeking board seats, pushing for a sale, opposing a merger, or simply investing. Amendments (SCHEDULE 13D/A) are filed when plans or holdings change materially.

Older filings

Schedules filed before the structured format (form types SC 13D and SC 13G) are text documents. They are in the filing index back to 1994, searchable with formType:"SC 13D", and readable with the download and full text search endpoints.

Ideas

• Alert when a known activist files a new 13D
• Track 13D/A amendments that change Item 4 language
• Combine with 13F holdings to see a manager's full position

Next steps

• Form 13D/13G API
• Datasets: Schedule 13D, Schedule 13G