(Corrects company ticker symbol for Taiwan Semiconductor to "2330.TW" from "2330.T" in fourth paragraph)
* Futures down: Dow 0.09 pct, S&P 0.15 pct, Nasdaq 0.18 pct
By Sruthi Shankar
April 19 (Reuters) - U.S. stock index futures edged lower on Thursday, as the effect of higher oil prices was offset by declines in chipmakers, following a weak forecast from Taiwan Semiconductor, the world's largest contract chipmaker.
Shares of Apple were also off 1.3 percent in premarket trading. Brokerage Mizuho Securities USA said weak demand for iPhone 8 models could dent the company's third-quarter forecast.
At 7:03 a.m. ET, Dow e-minis were down 23 points, or 0.09 percent, S&P 500 e-minis fell 4 points, or 0.15 percent and Nasdaq 100 e-minis dropped 12.25 points, or 0.18 percent.
Taiwan Semiconductor (TSMC), which is also an Apple supplier, lowered its own full-year forecast due to softer demand for smartphones and cut its outlook for global semiconductor industry growth this year.
TSMC's shares fell 4.3 percent, leading a host of chipmakers lower. Among them AMD and Nvidia fell about 1.6 percent, while Intel was off 0.4 percent.
Still not all reports were gloomy. American Express was up 3.6 percent after the credit card issuer easily topped Wall Street profit estimates.
Alcoa rose 5.4 percent after the aluminum producer reported strong results and raised it full-year earnings forecast.
Shares of metals including aluminum, nickel and iron ore have soared in the aftermath of U.S. sanctions on major Russian aluminum producer Rusal, driving up commodities and resources stocks globally.
Of the 52 companies among the S&P 500 that have reported first-quarter earnings through Wednesday, 78.8 percent topped profit expectations, according to Thomson Reuters data.
Overall profits at S&P 500 companies is expected to have increased 19.4 percent in the first quarter, the biggest in seven years.
Oil prices rose to their highest since late 2014 after sources told Reuters top exporter Saudi Arabia would be happy to see crude rise to $80 or even $100 a barrel and as U.S. crude inventories declined. (Reporting by Sruthi Shankar in Bengaluru; Editing by Shounak Dasgupta)