Twitter’s largest acquisition to date, of the adtech business TellApart, has turned out to be a little less big than originally thought. Back in April 2015, it was calculated that Twitter would pay nearly $533 million for TellApart based on the company’s share price at the time. But a 10-K report published today notes the final numbers: It was nearly $54 million lower, at $479.1 million, with $395 million of that recorded as goodwill.