If you are considering getting a medallion signature guarantee online and wondering whether it is legitimate, that is a perfectly reasonable question. Medallion guarantees involve sensitive financial documents — stock certificates, estate transfers, account ownership changes. The stakes are real, and if you have never heard of an online medallion service before, skepticism is healthy.
Here is what you need to know.
The Short Answer
Yes, an online medallion signature guarantee is legitimate — provided the service is an authorized participant in one of the three recognized medallion programs. The stamp carries the same legal weight regardless of whether it was applied at a bank branch or by an online service. Transfer agents do not differentiate between the two.
How Medallion Programs Work
Medallion signature guarantees can only be issued by financial institutions that are members of one of three programs recognized under SEC Rule 17Ad-15:
- STAMP (Securities Transfer Agents Medallion Program) — the largest program, whose members include banks, broker-dealers, and trust companies
- SEMP (Stock Exchanges Medallion Program) — members include regional broker-dealers and banks
- MSP (New York Stock Exchange Medallion Signature Program) — members include NYSE member firms and banks
Membership is not automatic. Institutions must apply, meet compliance requirements, and maintain a surety bond. The bond exists to back the guarantee — if a stamp is applied to a fraudulent signature, the guarantor is financially liable.
This framework applies equally to banks, brokers, and online services. The authorization comes from program membership, not from the physical location where the stamp is applied.
Why Transfer Agents Accept Online Stamps
Transfer agents — Computershare, EQ (formerly Equiniti), AST, BNY Mellon, Continental Stock Transfer, and others — process securities transfers based on the medallion stamp itself. They verify:
- That the stamp comes from a recognized program participant
- That the stamp includes a valid identification number
- That the guaranteed value covers the transaction
They do not verify whether the customer walked into a bank branch or submitted documents through an online platform. The stamp is the stamp.
This is an important distinction. A medallion guarantee from an online service that is a STAMP participant is identical in legal standing to one from Bank of America or Fidelity.
How to Verify an Online Service Is Authorized
Before using any online medallion service, you should verify that it is a legitimate participant in a recognized medallion program. Here is how:
Check for STAMP program membership. The service should explicitly state which medallion program they participate in. If they cannot tell you, that is a red flag.
Look for surety bonding. Program participants are required to maintain a surety bond. A legitimate service will reference this.
Check their track record. How long have they been operating? How many stamps have they issued? Are their stamps accepted by the transfer agents you need?
Look for real information about who runs the company. Legitimate services will have an about page with real names, real backgrounds, and real contact information.
Search for independent references. Transfer agents, financial advisors, and estate attorneys who recommend the service are a strong signal.
About eSignature Guarantee
eSignature Guarantee is an authorized participant in the Securities Transfer Agents Medallion Program (STAMP). Here are the facts:
Operating since 2017. We have been providing medallion signature guarantees for over eight years.
Over 25,000 stamps issued. Our guarantees have been accepted by every major transfer agent in the country.
Bonded and insured. We maintain a surety bond as required by the STAMP program, plus professional errors and omissions insurance.
Founded by securities professionals. The company was founded by Seth Farbman, a securities lawyer and owner of V Stock Transfer (an SEC-registered transfer agent), and Yoel Goldfeder, a corporate and securities attorney. In July 2025, the company was acquired by Jess Heron, whose background includes fintech roles at Ripple, Circle, and Pivotal.
Accepted everywhere. Our stamps are accepted by Computershare, EQ, AST, BNY Mellon, Continental Stock Transfer, and all other major transfer agents.
You can learn more about the team on our About page and read about our process at Is eSignature Guarantee Legitimate?
How the Process Works
Our process is designed to be thorough, not just fast. Every transaction goes through:
-
Identity verification. You create an account and complete biometric identity verification. We confirm you are who you say you are before reviewing any documents.
-
Document submission and review. You submit the documents that need to be stamped along with supporting documentation for your transaction type. Not sure what you need? Use our interactive questionnaire to find out.
-
Compliance review. A dedicated compliance officer reviews everything — identity, authority, document completeness. If something is missing, we contact you promptly.
-
Medallion stamp applied. Once approved, we apply the physical stamp. Each stamp includes a unique identification number that can be verified by the receiving transfer agent.
-
Documents returned. Stamped documents are shipped back via 2-day shipping, with scanned copies sent by email.
We accept liability for every signature we guarantee. That liability is what makes the stamp meaningful, and it is why we take the review process seriously.
What If Something Goes Wrong?
If a transfer agent rejects a submission for reasons unrelated to the stamp — a form filled out incorrectly, a missing document, a procedural issue on their end — we work with you to resolve it. If documents need to be re-stamped due to a correction on the same transaction, we do not charge again.
If we cannot complete your medallion guarantee for any reason, we provide a full refund.
Red Flags to Watch For
Not every online service claiming to provide medallion guarantees is legitimate. Be cautious of:
- Services that cannot name which medallion program they participate in
- Unusually low prices (the compliance and liability costs are real)
- No verifiable information about the company, team, or track record
- No clear process for identity verification and document review
- Guarantees that sound too fast or too easy (a proper review takes time)
A legitimate medallion guarantee service will be transparent about who they are, how they are authorized, and what the process involves.
The Bottom Line
An online medallion signature guarantee is as legally valid as one from a bank — as long as the service is an authorized participant in a recognized medallion program. The stamp is the stamp, and transfer agents do not care whether you visited a branch or submitted documents online.
eSignature Guarantee has been providing this service since 2017, with over 25,000 stamps accepted by every major transfer agent. Your skepticism is reasonable. We hope the facts speak for themselves.