Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

According to stock index futures as of 7:50 a.m. EDT, the Dow Jones Industrial Average (DJINDICES:^DJI) will open lower this morning, falling by 87 points at the start of trading. U.S. lawmakers have made no progress toward a deal to reopen the government, which isn't very reassuring as we approach a critical deadline on the debt ceiling that will require cooperation between the parties in Congress.

World markets traded lower overnight, led by a 2% drop in Japan's Nikkei index.

ADP employment figures this morning showed that private sector jobs increased by 166,000 in September, a bit below expectations and roughly equal to August's increase.

With those broader trends in mind, here are a few individual stock stories to watch for in today's market.

Some Microsoft (NASDAQ:MSFT) shareholders want Bill Gates out. Three investors, who together own more than 5% of the company, are pushing for Gates to step down from his position as chairman, according to Reuters. The shareholders want whoever replaces Steve Ballmer as CEO to be free to make wholesale changes at Microsoft, which might not be the case so long as Gates leads the board of directors. The investor grumbling highlights the uncertainty around Microsoft's new strategic direction as it hunts for its next CEO. Shares are unchanged in premarket trading.

Former Dow component Alcoa (NYSE:AA) could see active trading today after Deutsche Bank downgraded the stock on account of falling aluminum prices. The firm slashed its 2013 earnings estimates almost in half, to $0.27 per share. Alcoa's stock is down 6% so far this year, and is currently lower by 2.5% in premarket trading.

Monsanto (NYSE:MON) delivered slightly worse-than-expected quarterly results this morning. The company booked a $0.47 loss on a minor revenue increase, to $2.2 billion. Monsanto also announced a $930 million acquisition of The Climate Corporation aimed at boosting its farming systems platform. Monsanto shares are down 3% in premarket trading.

Finally, Global Payments (NYSE:GPN) should see a boost today after it reported surprisingly strong revenue and profit last night. The company managed 7% sales growth and a 15% spike in earnings per share. Global Payments also raised its EPS guidance for the year, although that was entirely due to an accelerated plan to repurchase its own stock. Shares are up 7% in premarket trading.