 Nuveen Asset Management LLC raised its stake in Gentex Co. NASDAQ:GNTX by 4.3 during the second quarter, HoldingsChannel reports. The fund owned 581,490 shares of the auto parts companys stock after buying an additional 23,934 shares during the period. Nuveen Asset Management LLCs holdings in Gentex were worth 14,985,000 as of its most recent SEC ... 