Nearly 60% of cost synergies from SBC's proposed acquisition of AT&T are expected to come from headcount reductions, said senior officials from both companies in a conference call from the investment community. SBC currently has about 163,000 employees, while AT&T has 47,000. The layoffs are likely to affect about 13,000 employees. The job cuts are expected to include 550 engineering positions, 1,100 enterprise data ordering positions, 1,200 enterprise data provisioning positions, 1,500 enterprise care functions, 700 network management...