Stock index futures rose slightly on Thursday as investors remained positive following an overall strong earnings season and ahead of results from United Parcel Service Inc and McDonald's Corp .

The Nasdaq clinched an 11-day winning streak on Wednesday, its longest such run since 1996, while the Dow industrials were weighed down by disappointing bank results and a slide in shares of energy companies.

Later on Thursday, other bellwethers including Microsoft Corp , American Express Co and Inc are also expected to report their quarterly scorecards.

Earnings could get choppy as this reporting season continues because the production side is stronger than the consumption side, and production-oriented companies tend to report sooner than consumer-oriented ones, said Douglass Cliggott, chief investment officer at Greenwich, Connecticut-based Dover Investments.

Bristol-Myers Squibb Co announced late Wednesday it will buy biotechnology company Medarex Inc . Medarex shares soared 90 percent on the buyout news.

S&P 500 futures were up 5.8 points and were above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures rose 17 points and Nasdaq 100 futures gained 6.25 points.

On the economic front, investors will look for clues on whether the pace of job cuts is slowing when the Labor Department releases first-time claims for jobless benefits for last week at 8:30 a.m. EST (1230 GMT). Economists in a Reuters survey forecast a total of 550,000 new filings compared with 522,000 in the prior week.

The National Association of Realtors releases existing home sales for June at 10 a.m. (1400 GMT). Economists in a Reuters survey forecast a 4.84 million annualized unit total versus 4.77 million annualized units in May.

* Shares of eBay Inc jumped more than 6 percent in premarket trading after the company reported on Wednesday results that beat market expectations.

(Reporting by Rodrigo Campos; Editing by Padraic Cassidy)