German stocks opened lower on Wednesday at the Frankfurt Stock Exchange. The DAX, index of 30 big companies, dropped 21.28 points, or 0.35 percent, to 6,138.23 at 09:04 local time. The index of medium-sized firms, MDAX, declined 35.25 points, or 0.42 percent, to 8,307.81. The TecDAX, the index of technology companies, dipped 13.96 points, or 1.70 percent, to 807.18. 