Why Is Superior Industries’ Stock Rallying? Last week, Mill Road Capital III, L.P., a Director of Superior Industries International (NYSE: SUP), bought SUP shares worth $943,000. Going by an SEC filing, the Director lapped up 188,600 shares of this manufacturer of bulk material processing and handling equipment at $5 per share on July 15. This attracted investors’ attention and SUP stock rose 5.8% to $4.20 on July 19 from the closing price of $3.97 on July 14. According to TipRanks, which also provides a comprehensive list of daily insider transactions, Mill Road Capital has lapped up SUP shares worth $1.88 million in the last two months.