Equibles

Top Institutional Holders

GetTopHolders

Read-only

Get the top institutional holders (fund managers) of an exact stock or ETF listing from SEC 13F-HR filings. Returns a ranked list by shares held, including published position value and percentage of total institutional 13F shares (not of shares outstanding). Values normally use report-date closing prices, may fall back to filer values, and can be zero when unavailable. During the newest quarter's filing window, non-ETF primary stocks carry non-filers' prior-quarter positions; ETF listings remain exact and as-filed because carry-forward is filer-wide. Use position type before treating put/call rows as ownership. Each holder shows its entity type from regulatory records (Form ADV, SEC filer profile, 13D/13G, N-CEN), filtered by holderTypes, and its style band measured from its filed book, filtered by styles.

Input Schema

Name	Required	Description
`offset`	No	Number of ranked holding rows to skip before returning results (default: 0)
`styles`	No	Style bands to keep, as an array of tokens: idx (index-like), sys (systematic-like), conc (concentrated), divact (diversified active), unk (book too small or unvalued to band), e.g. ["conc"]. Bands are measured from each holder's filed 13F book in the newest measured quarter on or before the report date; a holder not measured that quarter is left out by any style filter. Omit for all.
`ticker`	Yes	Listed security ticker (e.g., AAPL, VOO)
`maxResults`	No	Maximum number of holding rows to return (default: 20, clamped to 1-500)
`reportDate`	No	Quarter-end 13F report date in YYYY-MM-DD format, e.g. 2026-03-31 (defaults to the latest available; an off-quarter date snaps to the nearest report on or before it)
`holderTypes`	No	Holder types to keep, as an array of tokens: adv (registered investment adviser), era (exempt reporting adviser), ia (other adviser), bank, ins (insurer), bd (broker-dealer), fund (registered fund), plan (benefit plan), nonus (non-US institution), hc (parent holding company or control person with no other type on record), unk (no deciding record yet), e.g. ["bank", "ins"]. Types come from Form ADV, SEC filer profiles, 13D/13G and N-CEN, never from names. Omit for all.

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedOct 20, 2026

changedInput schema / properties / holderTypes / description

Previous value: -"Holder types to keep, as an array of tokens: adv (registered investment adviser), era (exempt reporting adviser), ia (other adviser), bank, ins (insurer), bd (broker-dealer), fund (registered fund), plan (benefit plan), nonus (non-US institution), unk (no deciding record yet), e.g. [\"bank\", \"ins\"]. Types come from Form ADV, SEC filer profiles, 13D/13G and N-CEN, never from names. Omit for all."New value: +"Holder types to keep, as an array of tokens: adv (registered investment adviser), era (exempt reporting adviser), ia (other adviser), bank, ins (insurer), bd (broker-dealer), fund (registered fund), plan (benefit plan), nonus (non-US institution), hc (parent holding company or control person with no other type on record), unk (no deciding record yet), e.g. [\"bank\", \"ins\"]. Types come from Form ADV, SEC filer profiles, 13D/13G and N-CEN, never from names. Omit for all."

Changed1 schema field changedOct 18, 2026

addedInput schema / properties / styles

Added value: +{
+  "default": null,
+  "description": "Style bands to keep, as an array of tokens: idx (index-like), sys (systematic-like), conc (concentrated), divact (diversified active), unk (book too small or unvalued to band), e.g. [\"conc\"]. Bands are measured from each holder's filed 13F book in the newest measured quarter on or before the report date; a holder not measured that quarter is left out by any style filter. Omit for all.",
+  "items": {
+    "type": "string"
+  },
+  "type": "array"
+}

Changed1 schema field changedOct 18, 2026

addedInput schema / properties / holderTypes

Added value: +{
+  "default": null,
+  "description": "Holder types to keep, as an array of tokens: adv (registered investment adviser), era (exempt reporting adviser), ia (other adviser), bank, ins (insurer), bd (broker-dealer), fund (registered fund), plan (benefit plan), nonus (non-US institution), unk (no deciding record yet), e.g. [\"bank\", \"ins\"]. Types come from Form ADV, SEC filer profiles, 13D/13G and N-CEN, never from names. Omit for all.",
+  "items": {
+    "type": "string"
+  },
+  "type": "array"
+}

Changed1 schema field changedSep 4, 2026

changedInput schema / properties / ticker / description

Previous value: -"Company ticker symbol (e.g., AAPL, MSFT)"New value: +"Listed security ticker (e.g., AAPL, VOO)"

Changed2 schema fields changedSep 3, 2026

changedInput schema / properties / maxResults / description

Previous value: -"Maximum number of holders to return (default: 20, clamped to 1-500)"New value: +"Maximum number of holding rows to return (default: 20, clamped to 1-500)"

addedInput schema / properties / offset

Added value: +{
+  "default": 0,
+  "description": "Number of ranked holding rows to skip before returning results (default: 0)",
+  "type": "integer"
+}

First observedJul 19, 2026

TDQS

A4.1/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only cover the safety profile (read-only, not destructive, not open-world), and the description adds substantial context they cannot: value fallback behavior, zeros when unavailable, carry-forward of prior-quarter non-filer positions during the newest filing window, and the ETF-vs-primary-stock distinction. This is exactly the extra behavioral context that annotations cannot carry.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Purpose is front-loaded and the dense paragraph is mostly high-value caveats (carry-forward, put/call, entity-type sourcing). It is long and somewhat crowded, and the closing sentences partially re-state filter semantics already in the schema, but no sentence is pure filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema and a complex 13F data model, the description does meaningful work describing the return shape (ranked list, position value, percentage of total institutional 13F shares rather than shares outstanding) and its caveats. Pagination is left entirely to the schema, so it is complete enough but not exhaustive.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents all six parameters in depth (including token lists for holderTypes and styles). The description largely restates those filters ('filtered by holderTypes', 'filtered by styles') and adds little syntax or format detail beyond the schema, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource with exact scope: 'top institutional holders (fund managers) of an exact stock or ETF listing from SEC 13F-HR filings'. The direction (holders OF a listing) clearly distinguishes it from near siblings like GetMostHeldStocks, GetFundsHoldingStock, and GetInstitutionPortfolio without needing their schemas.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is implied by the resource and by data-semantics cues ('Use position type before treating put/call rows as ownership', quarter-filing-window behavior), but no alternative tool is ever named and there is no explicit when-to-use/when-not statement. Minimum-viable context rather than routing guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

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