Avenue 81, Inc (DBA LeadBrite) which operates several lead page services, announced in December 2015 a new service called “Center” and was looking for early users. At the time, they were using the domain name Center.io but have now done a domain name upgrade and acquired the premium generic domain name Center.com from past owner Horoscope.com Inc. according to whois records.
According to a MarketingLand.com article about Center, they offer a lead management tool.
On February 10, 2016 the domain name Center.com switched to Sedo Transfer service and by February 19, 2016 displayed Avenue 81, Inc in whois records. This would indicate that the purchase may have taken place via Sedo or Sedo simply handled the escrow portion of the domain sale. I did not see Sedo report the sales price for the domain.
Center.com is now redirecting to Center.io but that will likely change in the near future when the service comes out of beta and the .com domain taking the lead.
To note: Avenue 81, Inc. was found guilty of reverse domain name hijacking for the domain name LeadPages.com, which they tried to obtain using a UDRP in January 2015.
If I had to guess what Center.com sold for, I would say about US$150,000-$300,000