As sports fans enjoy the legacy-defining moments of this month’s N.B.A. finals and Stanley Cup finals, Jason Arasheben is studying like a college student before exams.

Arasheben, a celebrity jeweler whose clients include the rappers Drake and ASAP Rocky, is investigating the history of the contending teams, the connections to their cities and any other interesting facts that could be infused into an extravagantly bejeweled ring. He is also scouring his personal contacts for anyone who could facilitate a meeting with the wealthy owners of the winning franchises.

“You just have to start connecting the dots,” said Arasheben, the chief executive of the Jason of Beverly Hills jewelry house near Los Angeles. “Billionaires talk to other billionaires.”

In the past few years, Arasheben has established himself as a go-to jeweler for title-winning teams — carving out a corner of the market long dominated by Jostens — by creating dynamic rings that include reversible faces and detachable compartments.

“He’s reimagined what the championship ring is all about,” said Eric Tosi, the chief marketing officer of the Vegas Golden Knights, who won the Stanley Cup last year.

“Every team that wins a title no matter the sport is going to get a ring,” Tosi continued. “But how can you stand out? How can you do something that’s never been done before? He’s done that.”