What do New York's most famous hotel, the Lloyd's of London building and the headquarters of the U.K.'s top law firm have in common? They are all owned by Chinese insurers.

This new breed of buyers, who weren't allowed to invest overseas before 2012, are flooding into the global market for prime commercial real estate after being given more freedom to deploy their $1.6 trillion of assets. That has meant good times for sellers of trophy real estate in major cities.

"It's becoming a seller's market now if you have a prime property," said David Green-Morgan, global capital markets research director at Jones Lang LaSalle Inc. "The new investors have helped push the prices higher in the bigger cities."