(Bloomberg) -- Two of the companies that emerged as key dealers of Russian oil following the invasion of Ukraine have had representatives in common, according to documents reviewed by Bloomberg News, offering a fresh glimpse into the little-known and opaque businesses.Most Read from BloombergChina Embassy Rips ‘Brutal’ Russia Border Incident in Rare MoveBerkshire Operating Earnings Jump on Insurance StrengthThe Most Dangerous Job for Lawyers Is Being on Trump’s Legal TeamProsecutors Alert Judge