The largest shareholder in Live Nation Inc said on Friday he is concerned about the role Barry Diller will play if the concert promoter merges with Ticketmaster Entertainment Inc.

Sam Shapiro, chairman in Shapiro Capital Management, which holds around 15 percent of Live Nation's outstanding shares, said he fully backs the merger and the management team led by Live Nation CEO Michael Rapino and Ticketmaster CEO Irving Azoff.

But he said in an interview he is concerned about Diller -- who will become non-executive chairman of Live Nation Entertainment -- because of his poor record on providing shareholder returns as CEO of IAC/InterActiveCorp.

IAC/InterActive spun off Ticketmaster last August, but Diller has retained an interest in the business.

"There's never been a question whether I think the combination of the two companies is a big positive," Shapiro told Reuters.

Shapiro said a report on Thursday that he opposed the deal did not fully reflect his opinion of the merger.

"As investment managers, we're interested in creation of shareholder value for our clients," he said. "I was worried about Barry Diller because shareholder return of value to his companies have not been that great."

Shapiro said Rapino had done "everything and more" to deliver value to shareholders and said that, as time goes by, he would be interested in increasing his firm's holding of Live Nation shares.

Shapiro Capital held 11.9 million Live Nation shares as of Dec. 31, according to a regulatory filing on Feb 3.