The NFL and Yahoo are crowing about a big turnout for the first global live Internet broadcast of one of the league’s games. Variety reports that the companies are claiming a turnout of 15.2 million unique viewers for the game in London between the Buffalo Bills and Jacksonville Jaguars, with about 10 million of those viewers in the U.S.

But the report notes that those numbers may not accurately reflect actual viewing of the game. Meanwhile, questions have also been raised about whether Yahoo might have lost money on the event.

“The game hit over 33.6 million total views across all devices on Yahoo and Tumblr, amounting to more than 460 million total minutes of the game,” Variety reports. “In part, Yahoo achieved those audience numbers by auto-streaming video on yahoo.com and in several of its apps, so it’s likely millions of users who didn’t even intend to watch the game caught a few minutes.”

Streaming-industry consultant Dan Rayburn says it’s not possible to calculate actual concurrent viewership on the basis of the numbers the NFL and Yahoo have released, according to the report. But Rayburn adds: “With it being auto-played on the homepage, (average viewing time) numbers would be skewed.”

Variety notes that a CNN analysis concludes that average viewing per minute was 2.36 million, well below typical TV numbers for the NFL. (As an example, ESPN’s “Monday Night Football” averages 13.5 million, Variety notes.)

“Yahoo had signed up about 30 advertisers, and guaranteed them an audience of at least 3.5 million,” Variety notes. “The Internet company paid an estimated $15 million to the NFL for the rights; that doesn’t include Yahoo’s costs for marketing, streaming bandwidth and what it paid CBS to produce it.”