What is the relationship between 'Berkshire Hathaway' and 'Warren Buffett' in the context of the input sentence.
Options: position held, director/manager, founded by, currency

For example, two notable value investors operate businesses that fall into this category -- Tom Gayner at Markel and Warren Buffett at Berkshire Hathaway ( NYSE:BRK-A ) ( NYSE:BRK-B ) .
director/manager