# What Is a Guarantee Signature?

Published: 2026-02-07
Author: Warren Team
URL: https://www.heywarren.com/blog/guarantee-signature

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Every year, thousands of investors miss a critical securities transfer deadline — not because of market volatility, but because of a missing stamp. That stamp is a **guarantee signature**, and without it, your transfer agent will reject the paperwork outright, no matter how legitimate your claim.

Many people assume a notary seal is all they need to transfer stocks or settle an estate. That misconception delays transfers by weeks and, in estate cases, can create legal complications that cost real money to unravel. The confusion is understandable — both services verify your identity, but they carry very different legal and financial weight.

In this guide, you will learn exactly what a guarantee signature is, how the medallion stamp program works, where to get one at no cost, and which specific transactions require it. By the end, you will be prepared to complete any securities transfer without unnecessary delays or rejected paperwork.

According to the Securities Industry and Financial Markets Association (SIFMA), U.S. transfer agents process over $500 billion in domestic securities transactions annually. A significant portion of those transactions require a medallion endorsement — making this one of the most practically important requirements investors rarely learn about until they need it.

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## What Is a Guarantee Signature?

A guarantee signature — formally known as a medallion signature guarantee — is an endorsement from an authorized financial institution certifying that your signature on a securities document is authentic and that the institution accepts direct financial [liability](/blog/examples-liabilities) if the [transaction](/blog/what-is-a-transactions) turns out to be fraudulent. Transfer agents require it to protect against forged transfers and unauthorized ownership changes.

![The three medallion programs that standardized signature guarantees in the early 1990s, with STAMP now dominant.](data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%20600%20211%22%20width%3D%22600%22%20height%3D%22211%22%20role%3D%22img%22%3E%3Ctitle%3EHierarchy%3C%2Ftitle%3E%3Crect%20width%3D%22100%25%22%20height%3D%22100%25%22%20fill%3D%22%23f8fafc%22%2F%3E%3Crect%20x%3D%22220%22%20y%3D%2220%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22%232563eb%22%2F%3E%3Ctext%20x%3D%22300%22%20y%3D%2254%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22700%22%20fill%3D%22white%22%3EMedallion%20Programs%3C%2Ftext%3E%3Cpath%20d%3D%22M%20300%2078%20L%20300%20105.5%20L%20120%20105.5%20L%20120%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%2240%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22120%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3ESTAMP%3C%2Ftext%3E%3Ctext%20x%3D%22120%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EMost%20widely%20used%3C%2Ftext%3E%3Cpath%20d%3D%22M%20300%2078%20L%20300%20105.5%20L%20300%20105.5%20L%20300%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%22220%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22300%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3ESEMP%3C%2Ftext%3E%3Ctext%20x%3D%22300%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EExchange%20members%3C%2Ftext%3E%3Cpath%20d%3D%22M%20300%2078%20L%20300%20105.5%20L%20480%20105.5%20L%20480%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%22400%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22480%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EMSP%3C%2Ftext%3E%3Ctext%20x%3D%22480%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3ENYSE%20firms%3C%2Ftext%3E%3C%2Fsvg%3E)

*The three medallion programs that standardized signature guarantees in the early 1990s, with STAMP now dominant.*

A standard signature simply proves you wrote your name on a page. A guarantee signature goes further: the issuing bank or brokerage puts real money behind the verification, agreeing to cover financial losses if the signature or transaction is later proven fraudulent. Coverage limits typically range from $100,000 at the lowest program tier to more than $1 million at the highest.

**How the medallion program was standardized**

The modern system emerged in the early 1990s through three industry programs:

- **STAMP** (Securities Transfer Agents Medallion Program) — the most widely used program in the United States, administered by Kemark Financial Services
- **SEMP** (Stock Exchanges Medallion Program) — historically used by stock exchange members
- **MSP** ([New York Stock Exchange](https://www.nyse.com/) Medallion Signature Program) — developed by the NYSE for member firms

Today, STAMP dominates. Participating institutions must meet net capital requirements, maintain qualifying insurance, and train authorized officers to issue the stamp. This is why not every bank branch — and not every teller within a qualifying branch — can provide the service.

The alphanumeric code embedded in the medallion stamp identifies the issuing institution and its coverage tier, giving transfer agents a way to verify authenticity and confirm the maximum guaranteed amount for that transaction.

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## Signature Guarantee vs. Notarization: Key Differences

A notarization confirms your identity at the moment of signing but creates zero financial [liability](/blog/examples-of-liabilities) for the notary. A signature guarantee, by contrast, means the issuing institution backs the transaction with its own capital. This financial accountability is the core reason securities transfer agents require a medallion stamp and will not accept a notary seal as a substitute.

![A notary verifies identity only; a medallion guarantee adds financial liability — the key distinction transfer agents require.](data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%20800%20210%22%20width%3D%22800%22%20height%3D%22210%22%20role%3D%22img%22%3E%3Ctitle%3EComparison%3C%2Ftitle%3E%3Crect%20width%3D%22100%25%22%20height%3D%22100%25%22%20fill%3D%22%23f8fafc%22%2F%3E%3Ctext%20x%3D%22230%22%20y%3D%2257.5%22%20text-anchor%3D%22end%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3ENotary%20Public%3C%2Ftext%3E%3Crect%20x%3D%22240%22%20y%3D%2225%22%20width%3D%226%22%20height%3D%2255%22%20rx%3D%226%22%20fill%3D%22%232563eb%22%2F%3E%3Ctext%20x%3D%22258%22%20y%3D%2257.5%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22700%22%20fill%3D%22%232563eb%22%3E0%3C%2Ftext%3E%3Ctext%20x%3D%22230%22%20y%3D%22152.5%22%20text-anchor%3D%22end%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EMedallion%20Guarantee%3C%2Ftext%3E%3Crect%20x%3D%22240%22%20y%3D%22120%22%20width%3D%22450%22%20height%3D%2255%22%20rx%3D%226%22%20fill%3D%22%237c3aed%22%2F%3E%3Ctext%20x%3D%22702%22%20y%3D%22152.5%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22700%22%20fill%3D%22%237c3aed%22%3E1.0M%3C%2Ftext%3E%3C%2Fsvg%3E)

*A notary verifies identity only; a medallion guarantee adds financial liability — the key distinction transfer agents require.*

### What a Notary Public Does

A notary public is a state-appointed official who witnesses document signings and verifies the signer's identity using a government-issued photo ID. Notaries are widely accessible — available at UPS Stores, law offices, banks, and online through remote notarization platforms. Their stamp is accepted for real estate deeds, affidavits, powers of attorney, and most legal documents.

However, a notary carries no financial responsibility for the underlying transaction. If a forged signature slips through, the notary faces no monetary obligation to the injured party. That gap in accountability is exactly why transfer agents do not accept notarizations for securities work.

### What a Guaranteed Signature Provides

A medallion signature guarantee provides a layered verification that goes well beyond checking an ID. The authorized officer will:

- **Verify your government-issued photo ID** against the name on the securities account
- **Confirm your ownership** of the securities being transferred by reviewing account records
- **Check the transaction amount** against the institution's current coverage tier
- **Apply a tamper-evident medallion stamp** with a unique alphanumeric code tied to the issuing institution
- **Accept financial liability** for the full transaction value up to the stamp's coverage ceiling

That liability-backed guarantee is what distinguishes the medallion from every other form of identity verification. Transfer agents can pursue the issuing institution directly if a fraudulent transfer slips through, which gives the entire securities transfer system its integrity.

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## How the Medallion Signature Guarantee Process Works

Getting a medallion signature guarantee involves contacting an authorized institution, presenting your identification and account documents, and signing the transfer form in front of a certified officer. The process typically takes 15 to 30 minutes when you arrive fully prepared, and most institutions complete same-day requests.

![The seven steps to obtaining a medallion signature guarantee, from choosing an institution to submitting your documents.](data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%20800%20149%22%20width%3D%22800%22%20height%3D%22149%22%20role%3D%22img%22%3E%3Ctitle%3ETimeline%3C%2Ftitle%3E%3Crect%20width%3D%22100%25%22%20height%3D%22100%25%22%20fill%3D%22%23f8fafc%22%2F%3E%3Cline%20x1%3D%22120%22%20y1%3D%2255%22%20x2%3D%22680%22%20y2%3D%2255%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%223%22%2F%3E%3Ccircle%20cx%3D%22120%22%20cy%3D%2255%22%20r%3D%2224%22%20fill%3D%22white%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22120%22%20y%3D%2260%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2215%22%20font-weight%3D%22700%22%20fill%3D%22%230f172a%22%3E1%3C%2Ftext%3E%3Ctext%20x%3D%22120%22%20y%3D%22101%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2212%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EFind%20institution%3C%2Ftext%3E%3Ctext%20x%3D%22120%22%20y%3D%22119%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EExisting%20account%20required%3C%2Ftext%3E%3Ccircle%20cx%3D%22260%22%20cy%3D%2255%22%20r%3D%2224%22%20fill%3D%22white%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22260%22%20y%3D%2260%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2215%22%20font-weight%3D%22700%22%20fill%3D%22%230f172a%22%3E2%3C%2Ftext%3E%3Ctext%20x%3D%22260%22%20y%3D%22101%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2212%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3ECall%20ahead%3C%2Ftext%3E%3Ctext%20x%3D%22260%22%20y%3D%22119%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EConfirm%20certified%20officer%3C%2Ftext%3E%3Ccircle%20cx%3D%22400%22%20cy%3D%2255%22%20r%3D%2224%22%20fill%3D%22white%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22400%22%20y%3D%2260%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2215%22%20font-weight%3D%22700%22%20fill%3D%22%230f172a%22%3E3%3C%2Ftext%3E%3Ctext%20x%3D%22400%22%20y%3D%22101%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2212%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EGather%20documents%3C%2Ftext%3E%3Ctext%20x%3D%22400%22%20y%3D%22119%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EID%2C%20statement%2C%20form%3C%2Ftext%3E%3Ccircle%20cx%3D%22540%22%20cy%3D%2255%22%20r%3D%2224%22%20fill%3D%22%232563eb%22%20stroke%3D%22%232563eb%22%20stroke-width%3D%223%22%2F%3E%3Ctext%20x%3D%22540%22%20y%3D%2260%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2215%22%20font-weight%3D%22700%22%20fill%3D%22white%22%3E4%3C%2Ftext%3E%3Ctext%20x%3D%22540%22%20y%3D%22101%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2212%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3ESign%20in%20person%3C%2Ftext%3E%3Ctext%20x%3D%22540%22%20y%3D%22119%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3ENever%20pre-sign%3C%2Ftext%3E%3Ccircle%20cx%3D%22680%22%20cy%3D%2255%22%20r%3D%2224%22%20fill%3D%22white%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22680%22%20y%3D%2260%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2215%22%20font-weight%3D%22700%22%20fill%3D%22%230f172a%22%3E5%3C%2Ftext%3E%3Ctext%20x%3D%22680%22%20y%3D%22101%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2212%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EOfficer%20applies%20sta%E2%80%A6%3C%2Ftext%3E%3Ctext%20x%3D%22680%22%20y%3D%22119%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EWith%20coverage%20code%3C%2Ftext%3E%3C%2Fsvg%3E)

*The seven steps to obtaining a medallion signature guarantee, from choosing an institution to submitting your documents.*

**Step-by-step walkthrough:**

1. **Start with institutions where you already hold accounts.** Banks, credit unions, and brokerages nearly always require an existing customer relationship before issuing a medallion stamp. Non-customers are routinely turned away.
2. **Call ahead to confirm availability.** Not every branch maintains a certified medallion officer. Calling first saves you a wasted trip.
3. **Gather your full document packet.** Bring a valid government-issued photo ID, your most recent account statement showing ownership of the securities, and the transfer form that needs the guarantee. For estate transfers, also bring the death certificate and letters testamentary. For name changes, bring the marriage certificate or court order.
4. **Do not sign the document beforehand.** This is the most common and costly mistake. You must sign in the presence of the officer — a pre-signed document will be rejected and you will need to obtain a fresh transfer form.
5. **Meet with the authorized medallion officer.** This person is specifically credentialed to issue the stamp, which sets them apart from standard bank tellers or customer service representatives.
6. **The officer applies the stamp and co-signs.** The medallion imprint, the officer's signature, and the alphanumeric coverage code are all applied at once.
7. **Submit promptly.** Most medallion stamps expire within 90 days of issuance. Submit your guaranteed documents to the transfer agent well before that window closes.

**Coverage tier limits**

If your transaction value exceeds the institution's stamp tier — for example, transferring $800,000 in securities to an account backed by a $500,000 tier — the guarantee technically does not cover the full amount. In that case, you need to seek a higher-tier guarantee from a larger participating institution. Confirm coverage tiers before your appointment.

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## Where to Get a Signature Guarantee

You can obtain a medallion signature guarantee at most major banks, credit unions, and full-service brokerage firms — but only as an existing account holder. The requirement for a prior customer relationship is not optional, so start by inventorying the financial institutions where you currently hold accounts.

### Banks and Credit Unions

Most large national banks participate in STAMP. JPMorgan Chase, Bank of America, Wells Fargo, and Citibank all offer the service to qualifying customers. The threshold for "qualifying" varies — some branches require a minimum account balance, a minimum length of relationship, or both.

Credit unions are often more accessible than large banks for this service. Members typically face fewer bureaucratic hurdles, and the service is frequently provided free of charge. Call your credit union's main office to find the nearest branch with a certified officer.

Community banks sometimes participate in STAMP and sometimes do not. If yours does not, ask whether they can refer you to a regional correspondent bank that does.

### Brokerage Firms

Full-service brokerages are often the fastest route to a medallion stamp, especially when the securities being transferred are already held in the account. Fidelity, Charles Schwab, Vanguard, Merrill Lynch, and Edward Jones all offer the service at their branch locations for account holders.

Online-only discount brokerages are less consistent. Robinhood and Webull, for example, do not operate physical branches, so in-person medallion services are unavailable. If your brokerage does not offer this service directly, their client support team can typically direct you to a partner institution.

**Fees**

Many institutions provide the medallion stamp free of charge to existing customers. Others charge a nominal processing fee, typically between $10 and $50. There is no federally regulated fee schedule, so ask your institution in advance.

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## When You Need a Guaranteed Signature

A guaranteed signature is required whenever you transfer registered ownership of securities, change account registration titles, or redeem physical stock certificates. The transfer agent's job is to ensure only the legitimate, verified owner can initiate these changes — and the medallion stamp is how they confirm that.

The most common triggering events include:

- **Transferring shares as a gift** to another individual outside of a standard brokerage transfer
- **Settling an estate** — moving securities from a deceased person's account to named beneficiaries
- **Redeeming physical stock certificates** issued before electronic recordkeeping became standard
- **Name changes on securities accounts** following marriage, divorce, or legal name change
- **Removing a joint account holder** or changing account registration type
- **Transferring assets under a court order** — judgments, settlements, or trust distributions
- **Moving assets from a self-directed IRA** to a beneficiary following the account holder's death

**When you do not need one**

Standard brokerage-to-brokerage account transfers using the Automated Customer Account Transfer Service (ACATS) do not require a medallion stamp. ACATS has its own electronic verification protocol. Similarly, most routine mutual fund exchanges within the same fund family do not require the guarantee.

However, if your transfer involves a title change, a physical certificate, or a partial transfer of a jointly held account, a medallion guarantee may still be required even within the ACATS system. When in doubt, contact the receiving transfer agent before initiating the process.

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## Common Mistakes That Delay Securities Transfers

The most frequent errors that cause transfer rejections are pre-signing documents, visiting a non-participating institution, letting the stamp expire before submission, and arriving without the full supporting document packet. Any one of these mistakes restarts the clock and can delay a transfer by four to six weeks.

**Pre-signing the document** is the single most common error. Transfer agents pre-print a clear warning on most transfer forms, but investors still sign at home out of habit. The moment the ink is on the page before the officer witnesses it, the form is void for medallion purposes. Request a new form and start over.

**Other costly errors to avoid:**

- **Assuming every branch qualifies.** Even at a participating bank, not every location maintains a certified medallion officer on staff. Always call ahead.
- **Ignoring the coverage tier.** A guarantee that does not cover the full transaction value of your transfer may be challenged by the transfer agent. Verify the tier matches your transaction amount.
- **Waiting until the last minute.** Medallion stamps expire — usually within 90 days. If you are working toward an estate deadline or a court-mandated transfer window, build in at least two to three weeks of buffer.
- **Bringing an incomplete document packet.** Transfer agents often require supporting documentation alongside the guaranteed form. For estate transfers, include the death certificate, letters testamentary, and any applicable court filings. Missing one document triggers a rejection of the entire packet.
- **Giving up after one rejection.** Some banks decline medallion requests based on account age, balance minimums, or internal risk policies. If your primary bank turns you away, try your brokerage or a credit union where you hold an account.

Starting the process three to four weeks before any hard deadline gives you the flexibility to resolve a rejection without missing a critical window.

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## Related Reading

**More from Warren**:
- [What Is a Jobber in Finance?](/blog/what-is-jobbers)
- [Obligors Explained: The Debtor at the Heart of Credit](/blog/obligor)
- [CADS: What Cash Available for Debt Service Means in Finance](/blog/what-does-cads-stand-for)

## Authoritative Sources

For deeper background and primary-source data on this topic, the following authoritative sources are useful starting points:

- [IRS](https://www.irs.gov/)
- [SEC](https://www.sec.gov/)
- [Federal Reserve](https://www.federalreserve.gov/)
- [Consumer Financial Protection Bureau](https://www.consumerfinance.gov/)
- [U.S. Department of the Treasury](https://home.treasury.gov/)

## Conclusion

A guarantee signature is a narrow but essential requirement in the world of securities ownership — one that trips up prepared investors every day simply because they did not know what to ask for or where to get it. Here are the key takeaways:

- A **medallion signature guarantee** is fundamentally different from a notarization — the issuing institution accepts direct financial liability for the transaction.
- You must be an **existing account holder** at the institution; walk-in requests from non-customers are almost always declined.
- **Never pre-sign the transfer document** — the signature must be witnessed by the certified officer at the time of the guarantee.
- Triggering events include estate settlements, name changes, physical stock certificate redemptions, and court-ordered asset transfers.
- The medallion stamp expires, typically within **90 days** — submit your paperwork to the transfer agent well within that window.
- If one institution declines, contact your brokerage or credit union — a relationship at multiple institutions gives you options.

Understanding the guarantee signature requirement before you face a deadline separates investors who navigate transfers smoothly from those who spend weeks correcting avoidable paperwork errors.

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