Warren Buffett needed just two weeks to put together Berkshire Hathaway Inc’s $11.6 billion takeover of Alleghany Corp, its largest acquisition in six years, even as he balked at paying the insurer’s banking fee, a regulatory filing on Monday shows.

Berkshire, which is based in Omaha, ultimately agreed to pay $848.02 per share, with the $1.98 difference from $850 accounting for Goldman’s fee.

The merger was announced on March 21. Alleghany got 25 days to potentially find a better offer. Goldman has since asked 31 potential bidders about their interest, the filing said. The “go-shop” period ends on April 14.

Read more: Reuters