Business is booming for Northborough-based National Card Investors

Jeffrey Weisenberg of National Card Investors.

By Melanie Petrucci, Senior Community Reporter

Northborough – Jeffrey Weisenberg of Northborough has a passion for baseball trading cards. 

He has been in the business since 1978 since he was just 10 years old. Now, with over 40 years of experience, Weisenberg isn’t slowing down.

“I love what I do,” he remarked. 

Having traded cards for years, Weisenberg formed his company, National Card Investors, in September of 1995.

Six years later, he became a high school computer science teacher at Doherty Memorial High School, his Worcester alma mater. 

“I’m a full-time high school teacher and a full-time baseball card dealer,” he said.

Luckily, though, Weisenberg loves both these jobs. 

“They don’t feel like work,” he said.

According to Weisenberg, the card and memorabilia market is massive, counting as a multi-million dollar, if not a billion-dollar industry. Right now, specifically, business is booming. 

“It’s a bull market,” he said.

Through his company, Weisenberg buys and sells sports memorabilia and collections from modern-day all the way back to the 1800s. That makes National Card Investors one of the biggest buyers of sports memorabilia in the country.

Weisenberg purchases inventory with the intention to resell, whether on eBay, his website or on online auctions.

In person, Weisenberg participates in the annual Greater Boston Sports Collectors Club Show held at the Shriners Auditorium in Wilmington, Mass. A trade show, this year’s event is scheduled for November 5 – 7, 2021.

Weisenberg says he has the capability to even buy million-dollar collections, dealing in cards, memorabilia, autographs and more. While his focus is on sports, he does “dabble in comics, coins, stamps and non-sport cards.”

“I have experts that I’ve known most of my life who are experts in those fields that take care of those items for me,” he noted. “I’m the sports memorabilia guy and it doesn’t have to be baseball, basketball, football or hockey. It could be golf, tennis, boxing, wrestling, Olympics – anything sports related.”

When asked what cards are hot right now, Weisenberg had a quick response.

“The modern guys,” he said. “Lebron James, Michael Jordan, Ja Morant, Mike Trout, all the big-name modern players are really hot.”

However, Weisenberg still concentrates on material focused more on the 1980s, 1970s and earlier. 

Weisenberg explained that because the market for cards and memorabilia is so good, now is the time to clean out the attic.

He is available for appraisals – free of charge, and he will offer his expert advice to help customers sell their items.

“It’s a great time for you to buy, and it’s a great time for you to sell,” he said. “If you’ve got your collection sitting in your attic, give me a call, and I’m happy to see what it’s worth.”

For more information, visit the National Card Investor website Weisenberg can be reached by phone: (508) 842-2324 or email: