Iβve been holding on to this hat forever!! Finally got the opportunity to get it signed NBA legend Alex English.. Courtesy of Powers Sports!
July 05, 2026 4 min read
If you're buying sports memorabilia, you've probably heard the term Certificate of Authenticity (COA) countless times. But what exactly does it mean, and how does it work?
A Certificate of Authenticity, often called a COA, is simply proof showing who authenticated an autograph or collectible. It tells collectors which authentication company examined or witnessed the signature so they can verify the item's authenticity.
Modern authentication has become far more secure than it was years ago, giving collectors greater confidence when buying autographed sports memorabilia.
Throughout the 1990s and even into the early 2000s, most certificates of authenticity were simply pieces of paper.
The problem?
Nothing physically connected that paper certificate to the signed item.
A paper COA could potentially be separated from one autograph and paired with another item. Because of this, paper certificates became much less reliable as the hobby grew.
Modern authentication companies solved this problem by attaching authentication directly to the collectible itself.
Nearly every major authentication company uses a tamper-evident hologram that's permanently attached directly to the signed item.
The hologram contains:
When you scan the QR codeβor manually enter the certification number on the authentication company's websiteβyou'll be taken directly to that item's verification page.
Major authentication companies include:
Their databases typically display information such as:
This makes verifying sports memorabilia easier and more secure than ever before.
A Letter of Authenticity (LOA) is different from a standard Certificate of Authenticity.
Rather than simply attaching a hologram to the item, the authentication company provides a detailed document that includes:
That photograph is extremely valuable because it permanently connects the autograph to the document.
If someone attempted to switch the certificate to another item, the photograph would immediately expose the mismatch.
LOAs are commonly issued after an item has been submitted to companies like:
for expert autograph examination.
Modern authentication systems provide multiple layers of protection.
Instead of relying on a paper document, collectors can verify:
These improvements make modern authentication significantly more secure than the paper certificates commonly used decades ago.
No.
Many witnessed autographs receive only a hologram and an online database entry.
A Letter of Authenticity is generally issued when an item has been submitted for an expert opinion rather than being witnessed during the signing event.
Both methods are legitimate forms of authentication, but an LOA provides additional documentation by including a photograph of the exact item.
Authentication helps collectors:
Whether you're collecting signed baseballs, jerseys, helmets, trading cards, photos, or tickets, authentication has become one of the most important parts of the modern sports memorabilia hobby.
A Certificate of Authenticity (COA) is simply a way of identifying who authenticated a piece of sports memorabilia.
While paper COAs were once common, collectors now rely on secure holograms, QR codes, unique certification numbers, and online databases from trusted companies such as Beckett Authentication, JSA Authentication, and PSA Authentication.
For items authenticated after expert review rather than witnessed in person, a Letter of Authenticity (LOA) provides even greater confidence by including a photograph of the exact signed item.
Understanding how these systems work can help you buy, sell, and collect autographed sports memorabilia with confidence.
A Certificate of Authenticity (COA) identifies the authentication company that verified a signed collectible and allows collectors to confirm its authenticity.
COA stands for Certificate of Authenticity.
Paper-only COAs are largely obsolete. Most major authentication companies now use holograms, QR codes, and online verification systems that are attached directly to the item.
The three most recognized authentication companies are Beckett Authentication (BAS), JSA Authentication, and PSA Authentication (PSA/DNA).
Scan the QR code if one is present or enter the certification number on the authentication company's website to verify the autograph or collectible.
A Letter of Authenticity (LOA) is a detailed authentication document that includes the certification number, item description, and often a photograph of the exact signed item.
Not necessarily. Both serve important purposes. However, an LOA provides additional documentation because it includes a photograph of the authenticated item.
Unfortunately, yes. Counterfeit holograms do exist. That's why you should verify the hologram, certification number, online database entry, and compare the autograph itself to known authentic examples whenever possible.
Many modern authentication stickers include QR codes, but not every authentication company or every generation of holograms does.
Authentication helps collectors verify authenticity, reduce fraud, increase buyer confidence, preserve resale value, and confidently build a collection of authentic sports memorabilia.
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Overall rating: 4.9 / 5 from 4942 reviews.
Iβve been holding on to this hat forever!! Finally got the opportunity to get it signed NBA legend Alex English.. Courtesy of Powers Sports!
Troy H. 5/5 Verified
Again, PSM did a great job!
Marc W. 5/5 Verified
Nice autograph by Roger Clemens himself. Thank you Matt Powers and his team for this signing event.
Raymond T. 5/5 Verified
Nice autograph by Cal Ripken Jr. Thank you Matt Powers and his team for this signing event.
Raymond T. 5/5 Verified
Nice autograph. Thank you Matt Powers and his team for this signing event.
Raymond T. 5/5 Verified
Another perfect autograph on my 3000 hit baseball. Always a great experience! Thanks again.
Robert L. 5/5 Verified
I've had this card since the age of 12. Never had the opportunity until now to get his RC signed. Thanks Matt for making this happen!!
Joseph M. 5/5 Verified
Once again, Matt and his team delivered a smooth, professional experience in obtaining a Dustin Pedroia autograph (with authentication) to a book already containing a number of Red Sox greatsβ signatures. I recommend Powers Spirts Memorabilia highly.
Edward P. 5/5 Verified
Great experience. Card was just as described. Excited to have this added to the collection.
Justin W. 5/5 Verified
Frank Thomas 1990 Topps Signed Baseball Rookie Card #414B Auto Graded Beckett 10
The COA was placed exactly where I wanted it and it turned out great. Always an easy experience.
Brian G. 5/5 Verified
An excellent experience with the team. The ball turned out perfectly. Easy to ship the ball in and it returned after signing without an issue.
Brian G. 5/5 Verified
Great place to do business with. Thank you!
Andrew G. 5/5 Verified
Fernando Tatis Jr 2019 Topps Baseball Rookie Card RC #410 Graded PSA 9 MINT
π such a nice autograph! Thank you!
Scott L. 5/5 Verified
Thank you for another awesome autograph!
Scott L. 5/5 Verified
Mr. Powers delivered on my request for this Cal Ripken jr. autograph. It was a nice size clean and perfect signature better than I expected. Mr. Powers team is quick to respond with any concerns you may have and keeps you posted on your item. I will absolutely be getting more signatures through them to finish my collection. I highly recommend Powers Sports to anyone that has any doubts. I use to do send ins with Steiner sports until he sold, to me Powers picked up where they left off and I couldnt be happier. Thank you
Nelson P. 5/5 Verified
Great experience as usual! Iβll definitely be getting more autographs in the future!!
Jason R. 5/5 Verified
As good as it gets
Jeffrey E. 5/5 Verified
Smooth transaction
Jeffrey E. 5/5 Verified
The process was smooth and easy as always.
David C. 5/5 Verified
Awesome!
Bryan L. 5/5 Verified
The color match ink auto looks great! Thanks!
Preston E. 5/5 Verified
A fantastic addition to the set. Bosh's autograph really pops on this one. Thanks!
Preston E. 5/5 Verified
This might be the only autograph of this card that has his whole auto on it. Great addition to the collection!
Preston E. 5/5 Verified
The COA wasn't close to where I asked for it to be placed. I'm not sure how this was missed but it was a bummer when I saw that.
Preston E. 1/5 Verified
This came back amazing! The autograph was very clean! Thanks!
Preston E. 5/5 Verified
This completes my set of sketch cards. It's been fun doing this.
Preston E. 5/5 Verified
This was just the COA. Thanks!
Preston E. 5/5 Verified
It's awesome to get this one back! Another added to the Collection.
Preston E. 4/5 Verified
Great job by Powers Sports once again! They were able to secure a great signature from Andy Reid on my trading card, using the exact type pen and the exact location that I requested. Accuracy and quality are their top priority!
Vincent G. 5/5 Verified
I submitted 2 cards to get them signed by Patrick Ewing himself. Thanks Matt Powers and his team for this signing event.
Raymond T. 5/5 Verified
Nice addition of Barry Bonds to my PC!
Michael R. 5/5 Verified
Great card and great place to do business with. Thank you!
Andrew G. 5/5 Verified
Ronald Acuna Jr 2018 Topps Living Baseball Rookie Card RC #19 Graded PSA 10
Loved it all.
John G. 5/5 Verified
Great experience as usual, highly recommend Powers
Jason K. 5/5 Verified
Great job by Matt and his team as usual
Jason K. 5/5 Verified
Matt and his team did it again. Highly recommend Powers to anyone looking for high end autographs
Jason K. 5/5 Verified
Matt and his team always do their best for their clients. Couldnβt be happier
Jason K. 5/5 Verified
Awesome experience as usual, I love my Jagr autograph!
Jason R. 5/5 Verified
Awesome experience as usual!
Jason R. 5/5 Verified
Great experience! I had never gotten any autographs through a signing like this before and I had a number of questions. Someone called me right back & couldnβt have been nicer. The customer service was outstanding every step of the way & I couldnβt be happier with the Reggie Jackson autographed ticket.
Landon G. 4/5 Verified
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