When the developer Bruce Ratner set out to buy the New Jersey Nets and build an arena for them in Brooklyn, he recruited Jay-Z, the hip-hop superstar who grew up in public housing a couple of miles from the site, to join his group of investors.
Mr. Ratner may have thought he was getting little more than a limited partner with a boldface name and a youthful following that could prove useful someday. But Jay-Z’s contributions have dwarfed the $1 million he invested nine years ago. His influence on the project has been wildly disproportionate to his ownership stake — a scant one-fifteenth of one percent of the team. And so is the money he stands to make from it.
Now, with the long-delayed Barclays Center arena nearing opening night in September and the Nets bidding in earnest for Brooklyn’s loyalties, Jay-Z will perform eight sold-out shows to kick things off. But away from center stage he has put his mark on almost every facet of the enterprise, his partners say.