Jersey Authentications
Whether you're evaluating a purchase, documenting your collection, or protecting your family's investment, authentication establishes provenance and preserves value
For Your Family
Collectors often tell me, "I don't need authentication—I'm never going to sell." But unless you're immortal, your collection will outlive you. Every collection eventually changes hands, whether through inheritance, estate liquidation, or unforeseen circumstances.
Without documentation, your family will be left guessing. I've been witness to widows who sell valuable jerseys for pennies on the dollar—not because the items weren't authentic, but because there was no way to prove it. Estates liquidated at garage-sale prices because heirs didn't understand what they had.
Your collection represents years of investment. Don't leave your family to sort it out alone.
Authentication is estate planning for collectors. Document available on request, please write to me.
Why Authentication Matters
Before You Buy: Conditional verification protects you from costly mistakes. Whether you're spending $500 or $50,000, an authentication gives you confidence in your purchase decision. If you are planning on buying something for which would want a refund for if it turned out to be not authentic-able, negotiate this aspect before sending money. You will want to specify reasonable time for the authentication to be performed.
For Your Collection: Documentation provides credibility and value. Authentication offers the provenance that serious collectors and future buyers expect. It's validation that what you own is what you believe it to be.
For Your Family: Authentication is estate planning for collectors. Don't leave your family guessing about what you've built. Authentication isn't just about proving something is real. It's about protecting value for the people who matter to you.
When should you get a professional opinion?
If you are buying a potentially valuable jersey and counting on it appreciating in value at a future date, you should consider a professional opinion. Conversely, If you are buying something common, or buying something with your heart and have no interest at all in what it could be worth to you (or to your heirs after you have passed), don’t bother. Things acquire value with age, because of scarcity and nostalgia. Getting a professional opinion on a common player’s jersey from five years ago may not be strictly “worth it” right now, but if the price of the evaluation gives you peace of mind, do it. And consider this: that jersey will likely be worth much more ten or twenty years in the future.
There are a number of reasons to have your jersey professionally authenticated, and some reasons why it might not make sense, those which I’ll cover at the end of this discussion.
When is an authentication not worthwhile?
Frankly, there are many jerseys that are not worth an independent authentication, only because the cost of the evaluation would not pay for itself in the immediate resale of the item. These include jerseys, say, post 1990 that were issued to players that nobody knows, and recent jerseys that come with a MLB authentication hologram and a reference in the MLB database. (Though, for famous players or jerseys from big events, many auction houses will still require an independent third party authentication to lessen the chance representing a fraudulent item.)
Authentication is a must if:
You are contemplating the purchase of an expensive, valuable item. Most reputable sellers will agree to allow you to professionally authenticate a jersey they are offering, with the right for you to return it if it does not pass authentication. My name and reputation are known in this hobby, and if they do not agree to this condition, you should probably seriously consider walking away.
If your jersey is of a notable player (not necessarily even a superstar) and you are planning to sell your jersey at a named auction house. Most auction houses will insist on an authentication, and if you don’t provide them with one they accept, they may offer to get it done for you, at your expense. If you rely on the auction house to do the step for you, you will pay the price they quote you, and some will not share the full results with you, especially if it does not pass. And you will generally not have an opportunity choose or to speak with the authenticator at all. If you are selling yourself, say on eBay, a trusted authentication is very helpful to get the true value of your item.
If you have jersey(s) in your collection of value, and care about your family. I usually hear, “I don’t need an authentication because am not planning on selling my collection”, but unless you are immortal, you are not going to live forever. These collectables will far, far outlive you. Your spouse, or worse, someone who doesn’t really care about you or your collection will be left to disburse it after you have gone. They will generally have no idea what to do with it, and it is likely to be sold for a fraction of its value. I dislike immensely talking with people who brag about what they “stole” from a widow.
If you are trying to get insurance on items in your collection. Insurers will not cover valuable items without some sort of authentication that allows them to estimate its value. You can’t get this proof after it has been ruined or stolen.
You are looking for possible recourse from a very recent purchase. If you recently bought a jersey and are suspicious of its pedigree, have it checked out. If you do it quick enough (while notifying the seller that you are doing it) you might be able to set your mind at ease.
My Qualifications
My expertise is Major League Baseball jerseys/pants with select Minor League Baseball items. This is where my reference collection, research, and decades of experience are concentrated. I've spent 25+ years researching and documenting MLB jerseys, work that culminated in the 5,500-page MLB Game Worn Guide reference series. My authentication credentials include:
Regular work with major auction houses
Reference collection of 1,000+ team-issued jerseys
Archive of nearly one million period photographs
Featured authentication work in The New York Times, USA Today, and Sports Illustrated
Author of the industry-standard MLB jersey authentication reference guide
It matters with whom you authenticate
Whether you are using me or not, check out the reputation of your authenticator. Perhaps visit internet forums to learn who others use, if they were getting an authentication done now. I emphasize this because there are some names in the business whose older letters are not valued by collectors today.
I am often asked it I authenticate for individuals or just auction houses. While several of the major auction houses use me as their authenticator; if you prefer, working directly with me can save you time and gives you the ability to talk with me about your evaluation, something that doesn’t happen when I authenticate for a third party.
How Authentication Works
Quick Look Service
Before investing in full authentication, you may want an initial assessment. The quick-look service tells you whether deeper evaluation is warranted or if there are immediate concerns.
Photo based evaluation: $75
In-hand evaluation: $125 + return shipping
I don’t provide free opinions or casual assessments. Just as you wouldn’t ask a doctor to diagnose a serious condition at a dinner party. Responsible authentication requires time, research, and professional skill.
Typical turnaround: one week. If you have time-sensitive needs, let me know when you contact me.
Document with more info available here
Scheduling a full authentication
Our end result is a full written Letter of Professional Opinion: A complete opinion document involves comprehensive examination:
Physical Inspection Light tables and UV examination reveal construction details, wear patterns, alterations, and historical changes.
Material Analysis I evaluate fabrics, stitching methods, tagging, and manufacturing characteristics against known examples from my massive reference collection.
Historical Research Team rosters, photographic archives, and manufacturer records help establish provenance and verify authenticity claims.
Comparative Analysis Your item is compared against documented examples to verify consistency with team-issue characteristics.
Documentation All findings are compiled into a detailed written report with supporting evidence.
Timeline: At most times of the year, I can turn around authentication work in six weeks or less. At worst 8 to 10 weeks is my target limit. I try not to hold other peoples valuable property here for any longer that need be. If you are sensitive to this I will allow you to schedule your authentication in advance. To do this we will pick a date at least six weeks out, and I will ask you to send a deposit to hold your place. With cases of scheduled authentications I try to turn them around in three weeks or less.
The Question of “Provenance”
A letter of provenance is most valuable when it closes a gap that physical evidence alone cannot. If a jersey lacks manufacturer tags, has been altered, or comes from an era where documentation is scarce, a credible firsthand account can be the difference between an inconclusive opinion and a confident one. Provenance is also particularly meaningful when the chain of custody is short and direct — a letter from a player's widow describing how she kept the jersey in a cedar chest for forty years carries real evidentiary weight, especially when the physical condition of the item is consistent with that story.
Where provenance adds the least value is when the item is already self-documenting — a jersey with intact and accurate team tagging, a clear manufacturer timeline, correct period construction, and corroborating photographic evidence doesn't need a letter to make the case.
Provenance also adds little when it comes from someone too far removed from the source, or when the physical evidence and the written account don't align. In those situations, a letter of provenance doesn't strengthen the authentication — it actually raises questions. The most important thing to understand is that provenance and authentication are complementary but separate things.
A great letter doesn't replace a thorough physical examination, and a thorough physical examination doesn't make a questionable provenance disappear.
View an example of a letter of provenance here.
What Is a Letter of Provenance?
A letter of provenance is a written statement from someone with direct, firsthand knowledge of a sports collectible's history — typically the original owner, a family member, a former player, clubhouse staff, or someone else who can speak to the chain of custody from the source. A well-written letter should clearly identify the item being described, explain how the writer came to possess it or have knowledge of it, and document any relevant dates, transactions, or circumstances that connect the item to its claimed origin. It should be written in plain, specific language — not vague generalities — and signed with the writer's full name and contact information. What it should not contain is speculation, second-hand claims, or statements the writer cannot personally verify. A letter that says "I was told this belonged to Willie Mays" carries almost no weight; a letter from a clubhouse attendant who personally handed the jersey to Mays before a game is a different matter entirely.
Notarization does not verify the truth of what a letter says — it only confirms that the person who signed it is who they claim to be. A notarized letter of provenance is more useful than an un-notarized one because it creates a formal, traceable record and signals that the writer stands behind their statement publicly. However, notarization alone does not make a weak provenance letter strong. A notarized statement full of vague or unverifiable claims is still a weak document. When provenance is solid, notarization adds a meaningful layer of credibility. When it isn't, no stamp in the world will fix it.
What You'll Receive from me
These provide you with:
Documentation that can be used for insurance purposes (click here for deep dive document)
Provenance for resale
Peace of mind for your collection
Protection for your family's investment
Examples of completed Letters of Opinion are available in the gallery. I have included examples of some very valuable jerseys as well as those that are of more common issue. Some of these letters incorporate complete documentation of restorations I have performed as well.
Full Letter of Opinion Includes:
Detailed physical description of the item
Analysis of materials, construction, and characteristics
Historical context (team, era, manufacturing details)
Comparison to known authentic examples
Professional opinion on authenticity
Supporting photographic documentation
My signature and credentials
If I also have performed any restoration concurrent with the authentication, I will provide details of the restoration steps as well as photos of the process.
Pricing
For authentication services, payment is required in advance. Authentication requires the same professional time and expertise whether findings are positive, uncertain, or negative.
Full Authentication
I use value-based pricing for authentication—the fee reflects what the service is worth to you, not just the time it takes me. I'm not going to charge you $300 to authenticate a jersey that's currently worth $400. But a high-value item warrants a proportionally thorough fee because the stakes are higher and the risk of sophisticated counterfeiting is much greater.
Pricing is tailored to each item based on several factors:
Age and rarity - Older items require extensive archival research and comparison to period examples from my reference collection.
Item value and player significance - High-value items and Hall of Fame players often have extra sample jersey made as gifts; and people make them for their own collections. They unfortunately also attract sophisticated counterfeiters. These players' items require extra scrutiny and take longer to properly evaluate than straightforward pieces.
History and alterations - Most MLB jerseys from the 1990s and earlier were reused in spring training or the minor leagues, where names and numbers were changed. Discovering and documenting these alterations is detective work that requires both time and expertise.
Available provenance - Items with unclear ownership history or questionable claims need deeper investigation.
Quick-Look Service, as described previously
Photo-based evaluation: $75
In-hand quick-look evaluation, if required: $125 + return shipping
This is where most authentications begin. Very frankly, I am not interested in wasting your money or my time with an item that I am very sure that I will not be able to authenticate. This document will tell you all you need to know about my Quick Look service. It has proven to be very popular and a fair way to start the journey.
Authentication fees typically range from $125 for straightforward recent jerseys to $1,500+ for rare, high-value, or complex items. When you contact me with details about your jersey, I'll provide a specific quote.
Payment is required in advance. Authentication requires the same professional time and expertise whether findings are positive, uncertain, or negative.
What If an Item Cannot Be Authenticated?
Authentication is like medical diagnosis—I examine, investigate, and analyze using my skill, experience, and reference materials. It takes just as long (if not longer) to determine that something cannot be authenticated as it does to confirm authenticity. Like a doctor, I charge for my time and expertise, not the result.
Understanding Authentication Findings
Authentication is not always black and white. Sometimes the available evidence supports a conclusion with high confidence. Other times, the evidence is incomplete or conflicting, and my findings must reflect that uncertainty.
I use precise language to communicate confidence levels:
"Consistent with team issue”;”Shows appropriate use” - high confidence based on all markers
"Appears to be" or "Likely" - strong indicators but some uncertainty
"Insufficient evidence to determine" - not enough information to conclude
Understanding "Game Worn" vs. "Team Issued"
For jerseys from 1987 onward, distinguishing between game-worn and team-issued can be extremely difficult. Teams began manufacturing extra jerseys specifically for the collector market, and some star players wore jerseys only once or twice before they were sold. Without specific provenance or photo matching, I may not be able to definitively declare a jersey "game worn" even when it shows all the characteristics of team issue. [Read my detailed explanation of this distinction and why it matters →] (coming soon)
My responsibility is very simple: to give you an accurate assessment based on available evidence. When I am unable to authenticate an item, you have two documentation options:
Full Written Analysis: If you need recourse with the seller (return rights, fraud claim), I provide complete written documentation. This report supports your case and explains the specific concerns.
Brief email Summary (reduced rate): If there is no recourse and you simply need to understand my findings, I provide an email explanation of my analysis without photos with a $25 credit from the quoted price.
My Integrity Commitment to the Hobby
I maintain detailed records of all items I evaluate for my own reference and research purposes. When an item cannot be authenticated, I provide my findings to the submitter with the expectation that they will use this information responsibly.
In some cases, items that cannot be authenticated receive a full writeup at the client's request so they can seek legitimate recourse with the seller. Other times a full writeup is not needed and the item will remain in a personal collection. Either way I'm willing to accommodate. Items that forego a full writeup receive a $25 credit.
Most importantly; authentication represents my professional opinion based on available evidence and current knowledge. Other experts may reach different conclusions. If you choose to seek a second opinion, I encourage you to share all prior evaluations—it's simply the right thing to do.
Cross-Reference to Restoration
Planning a Restoration?
Authentication should happen BEFORE restoration begins. Restoration work—even when done correctly—can obscure or destroy provenance markers. Having authentication documentation before restoration protects your investment and preserves the historical record. [Learn about restoration services →]
Photo Matching
Photo-matching is not a service I personally offer. It's a specialized discipline that attempts to match a specific jersey definitively to media photos or broadcast images through exhaustive research of photo and video archives.
If you're interested in photo matching, I strongly recommend completing a standard authentication first. Photo matching can add significant value to an already-authenticated item, but it's not a substitute for fundamental authentication. Photo matching also involves significant cost whether or not a match is found.
If you're interested in photo matching services, I can provide referrals to reputable providers.
Brief Legal Stuff
My judgements on authenticity of jerseys are strictly offered as my professional opinions, based on my experience and information I have at the time of a review. My liability is limited to the price paid for my opinion. All my opinions are noted with the date they are offered, and I can’t be responsible for information that may come to light about the provenance of an item after my opinion has been documented. All evaluation data and the contents of letters of opinion remain my property.
Ready to get started?
What to Send Me in email:
Clear, detailed photographs (front, back, interior tags, any areas of concern)
Any provenance information you have (where/when purchased, previous owners, documentation)
What you want to accomplish (purchase verification, collection documentation, estate planning)
All authentication inquiries are handled via email for accurate record-keeping and proper documentation.
If we decide to proceed, you will need to get your jersey in my hands. I will not do authentications from photos, without exceptions. You are responsible to have your own insurance for any collectable item you are sending to me. Yes, I have insurance, but it might not be enough to cover the full cost of very valuable items sent to me, should the worst-case occur. While 95% of the time, collectors use common carriers (FedEx, UPS and US Post Office Priority Mail, insured and tracked with signature on receipt ) some use private couriers or bring it to me themselves. I will also travel to authenticate collections, if that is warranted.
Because I almost always have a backlog of work. I will tell you the estimated schedule time to begin your work. You might decide to send your jersey(s) now and wait, or you might want to work with me and schedule the work so you can send it just in time to be evaluated. We can discuss the specifics of this, if you are interested.
I am glad to discuss your options and answer your questions. Please contact me at bill@TheDream.Shop.