What is a Schedule 13D/A filing?

A 13D/A is an amendment to a previously filed Schedule 13D, the form used by holders of more than 5% of a US public company's class of stock when they have governance involvement. Amendments are required within 10 days of any material change to the disclosed beneficial ownership or stated plan, including significant share movements (typically 1% of class or more).

How is a 13D/A different from a 13G/A?

13D is filed by holders with governance intent (active stake). 13G is filed by holders without governance intent (passive 5%+ position). Both have amendment versions ending in /A. The choice between them is driven by stated plan, not stake size: a passive index fund at 8% files 13G/A, while a founder family at 8% files 13D/A because of governance involvement.

Why is the percent-of-class number on a 13D/A potentially misleading?

Percent of class is sensitive to denominator changes. If the company executed a stock buyback in the period, the percent of class may rise even though the filing person did not add shares. If the company issued a secondary or stock split, the percent of class may fall even though the filing person did not sell. Cross-check the share count column directly to read intent.

What does a Form 4 'E' transaction code mean alongside a 13D/A?

Code E is the expiration of a derivative security. When it appears alongside an open-market sale (S code) on a similar share count, it typically describes the cash-settlement leg of a forward sale contract being executed. The forward was struck previously; the derivative expires; the matching shares are delivered (or sold to settle the contract) on or around the expiration date.

How do I tell whether a founder is exiting versus monetizing?

Look at three things together: the size of the percent-of-class change (small = monetization, >5% = exit signal), whether the underlying Form 4 includes derivative expirations or 10b5-1 plan footnotes (suggests structured monetization), and the absence or presence of further 13D/A amendments in the following 60-90 days (quiet period = one-time event, repeated amendments = sustained unwind).

How can I cross-check a founder 13D/A against the institutional read?

Wait for the next quarterly 13G/A from the largest active institutional holder of the same stock. If the active manager is adding in the quarter following the founder's transaction, they are using the founder's monetization as a buying opportunity. If they are trimming, they are confirming the founder's view. Ignore passive index fund 13G/A movements for this cross-check — they are mandate-driven, not view-driven.

Where can I find historical 13D/A filings for a specific founder family?

On 13F Insight, the insider profile page (e.g., the Garcia II profile under /insiders/garcia-ernest-c-ii-0001017608) surfaces all Form 4 filings by the reporter. The accompanying 13D/A filings are accessible via SEC EDGAR's company-by-CIK browse interface using the same CIK. The institutional signal feed also flags 13D/A amendments as they cross our ingestion pipeline.

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Founder-Controlled Cap Tables: Reading 13D/A Family Block Filings

When a founder family files a Schedule 13D/A reflecting a major share movement, the percent-of-class line tells one story and the underlying transactions tell another. Here is how to read both without confusing structure for sentiment.

By Sarah Mitchell, Education Editor

PublishedMay 11, 2026UpdatedMay 11, 2026

When a founder or founder family files a Schedule 13D/A (an amendment to an original 13D), they are doing two things at once: reporting a change in their beneficial ownership of a US public company, and confirming that they remain (or have ceased to be) a 5%+ holder with the obligation to report material activity within 10 days.

For readers tracking founder activity, 13D/A amendments are the cleanest single document for understanding what happened to the family's stake. But they are also one of the most commonly misread filings, because the headline percent-of-class number compresses several distinct mechanisms into one line.

What A Schedule 13D/A Reports

A 13D/A reflects an updated snapshot of the filing person's (or group's) beneficial ownership of the relevant class of stock, expressed as both an absolute share count and a percent of the class outstanding. It also includes (or references) the underlying transaction(s) that triggered the amendment.

Two readings to do in order:

Read the percent of class. This is the headline. It tells you the family's current ownership share.
Read the underlying transactions. These are typically referenced via accompanying Form 4 filings (for transactions executed by reporting persons subject to Section 16) or via narrative disclosure within the 13D/A's Item 5 (transactions in the past 60 days).

The most common reader error is to stop at step 1. The percent of class is sensitive to denominator changes: if the company executed a buyback, the percent of class may have risen even though the family didn't add a single share. Conversely, if the company issued a large secondary, the percent of class may have fallen even though the family didn't sell.

A Worked Example: Carvana Family Block

On May 1, 2026, Ernest Garcia II, co-founder of Carvana, filed a 13D/A reporting the family group's beneficial ownership at 22.9% (42,442,317 shares). The same day, the Form 4 attached to the same SEC accession reported two open-market sale tranches totaling 4,000,000 shares — 2 million at $500 and 2 million at $450 — alongside a 4-million-share derivative expiration (transaction code E) at a $400 strike from April 17.

Reading the 13D/A in isolation, you see a 22.9% family stake. Reading the Form 4 alongside it, you see that the same accession encodes a $1.9 billion liquidity event for the family. Both numbers are correct, but the interpretation of either alone is incomplete:

The 22.9% figure tells you the family remains a defining holder with governance impact.
The $1.9 billion sale tells you they monetized a meaningful slice of the position via a structured transaction (the matched derivative expiration suggests a forward sale contract being settled).

A reader who only looks at the 13D/A line may conclude nothing changed. A reader who only looks at the Form 4 may conclude the family is exiting. The truth — a structured partial monetization that retains governance-defining ownership — requires both documents.

Why Founder Cap Tables Look Different From Institutional Cap Tables

For most US public companies, the largest holders by 13F are passive index funds and large active managers. BlackRock at 7.6% or Vanguard at 11.86% in any given S&P 500 issuer is a routine reality of index-fund mandates, not an active investment view.

Founder-controlled cap tables look different. The founder family's block (often disclosed via 13D rather than 13G because of governance involvement) is typically concentrated, illiquid relative to its size, and structurally tied to the family's control mechanisms — voting trusts, dual-class stock, family limited partnerships, or charitable foundations. Carvana's Garcia family block at 22.9% is roughly twice the size of the largest institutional active-manager position (T. Rowe Price at 12.6%). The family block defines governance; the institutional block defines marginal price discovery.

Form 4 Codes That Trigger 13D/A Amendments

Not every Form 4 transaction triggers a 13D/A. The threshold is generally a 1%-of-class change (or any change that affects the disclosed plan/intent). Common Form 4 codes that show up in the same accession as a 13D/A include:

Form 4 code	What it means	13D/A read
S	Open-market sale	Discretionary, depending on 10b5-1 plan footnote
P	Open-market purchase	Almost always discretionary
E	Expiration of derivative	Often the cash settlement of a forward sale
G	Gift / transfer	Could be charitable, family trust, or estate planning
D	Disposition (non-market)	Often administrative — secondary offering, in-kind distribution
C	Conversion	Class B → Class A typically; not a market signal

The Forward Sale Contract Pattern

A founder selling 2 million shares at $500 and 2 million shares at $450 on the same day, with a matching 4-million-share derivative expiration (code E) at a $400 strike disclosed in the same accession, is almost always describing a previously-executed forward sale contract being settled. The founder agreed at some prior date to deliver 4 million shares at a forward price; the underlying derivative expired on April 17; the cash-settlement leg was executed on May 1 at the spot prices that satisfied the contract terms.

This matters for interpretation. A forward sale is a planned monetization, often executed for tax-efficiency, diversification, or estate-planning purposes — not a discretionary panic sell. The two-tranche pricing structure at distinct prices above the live market is the giveaway.

Reading Subsequent 13D/A Filings

After the initial 13D/A, watch for the next amendment within the typical 90-day window. Material decreases in the family's percent of class (more than 1%) would change the governance calculus. Material additions (rare for founder-led monetization patterns) would reverse the read.

Crucially, a long quiet period after the initial 13D/A — no further amendments for several quarters — is often the most important signal. It indicates the family's monetization was a one-time structured event, not a multi-quarter unwind. The structured monetization plus quiet-period pattern is the most common founder-controlled cap table pattern across US growth-equity and PE-backed IPO names.

How To Cross-Check Against Institutional Reads

The best cross-check on a founder 13D/A is the next quarterly 13G/A from the largest institutional active-manager holder. If the active institutional manager (not the passive index funds) is materially adding to their position in the quarter following the founder's monetization event, the institutional community is reading the founder sale as a buying opportunity. If the active institutional manager is trimming, they are confirming the founder's read.

Passive index funds (Vanguard, BlackRock Fund Advisors, State Street SSGA) hold positions because of mandate, not view, and their 13G/A movements are not informative for this cross-check. Look only at active institutional 13G/A activity to read the institutional-vs-founder dialogue.

A Practical Reading Routine

For any founder-controlled cap table you care about:

Pull the most recent Schedule 13D/A from the SEC EDGAR page for the relevant filer.
Read the percent of class and absolute share count.
Open the matched Form 4 from the same accession (or any Form 4 filed within 10 days prior).
Read the transaction codes and identify whether the activity is open-market, structured, gift, or conversion.
Cross-check the change in percent of class against any company buyback or share issuance activity in the same window.
Wait for the next quarterly 13G/A from the largest active institutional holder to read the institutional response.