* Futures down: Dow 29 pts, S&P 2.5 pts, Nasdaq 24.25 pts
By Sruthi Shankar
Dec 6 (Reuters) - U.S. stock futures pointed to losses at the open on Wednesday as high-flying technology stocks fell for the fourth day on worries over lofty valuations and the impact of a tax overhaul on corporate earnings.
* The Nasdaq Composite index lost 1.6 percent in the past three days, its worst such fall in more than three months.
* Tech giants Apple, Microsoft, Facebook were all down between 0.53 percent and 0.73 percent in premarket trading.
* Other major decliner was Home Depot, which lost more than 1 percent after the home improvement chain announced a $15 billion share repurchase plan.
* The S&P technology index has risen about 34 percent this year and was down nearly 4 percent over the past week as investors shifted money to banks, retailers and other stocks that could benefit the most from corporate tax cuts.
* The bill passed on Saturday by Republican senators included a last-minute change to retain the corporate alternative minimum tax, or AMT, which had initially been removed.
* Including the AMT could negate parts of the bill seen as beneficial to tech companies and other corporations.
* The ADP National Employment Report, due at 8:15 a.m. ET (1345 GMT), is expected to show U.S. private employers added 185,000 jobs in November, compared with a gain of 235,000 jobs in previous month.
* Among other early movers, Bill Barret slipped more than 11 percent after the oil and gas producer agreed to buy Fifth Creek Energy for about $649 million.
* AeroVironment surged 23.5 percent after the drone maker reported surprise quarterly profit, helped by higher gross margin.
Futures snapshot at 7:00 a.m. ET:
* Dow e-minis were down 29 points, or 0.12 percent, with 25,990 contracts changing hands.
* S&P 500 e-minis were down 2.5 points, or 0.1 percent, with 169,943 contracts traded.
* Nasdaq 100 e-minis were down 24.25 points, or 0.39 percent, on volume of 46,300 contracts. (Reporting by Sruthi Shankar in Bengaluru; Editing by Arun Koyyur)