(Flickr/Bob Adams)
Stocks closed the session in the red but above the worst levels of the day, with the energy sector leading losses on the S&P 500. Crude oil prices fell to fresh lows.

First, the scoreboard:

• Dow: 17,598.20, -91.66, (-0.52%)
• S&P 500: 2,098.04, -5.80, (-0.28%)
• Nasdaq: 5,115.38, -12.90, (-0.25%)

And now, the top stories on Monday:

1. Oil fell to new lows on oversupply and weak demand concerns. West Texas Intermediate crude oil tumbled 4% below $45 per barrel for the first time since mid-March. Brent crude, the global benchmark, fell by about 5%, and below $50 for the first time since January. Iranian state media reported that the country could start increasing oil production as soon as one week after economic sanctions are lifted. And, China's official PMI gauge of manufacturing fell to a two-year low of 50.0. That adds to concern that demand from the world's second-largest oil consumer may slow.
2. US manufacturing numbers kicked off a crucial month for economic data. The Institute of Supply Management's manufacturing report leaked, and came in at 52.7 for July, below the estimate of 53.5, which was also the reading for June and a year-to-date high. "Looking ahead, the manufacturing sector will probably continue to struggle as the dollar has appreciated further recently and overseas demand has remained muted," Capital Economics' Adam Collins wrote in a note to clients.
3. Markit Economics' purchasing manager's index (PMI) came in at 53.8 for July, in line with estimates. The manufacturing report was strong overall, with production volumes rising at the fastest pace in three months, and incoming new work growing at the fastest pace since March. But taking a step back, Markit chief economist Chris Williamson said in the release, "the sector continues to endure one of the slowest growth phases seen over the past year and a half."
4. Greek stocks got slammed after opening for the first time in five weeks. The Athens Stock Exchange (ASE) index fell by up to 23%. In a stunning data development, Greece's PMI fell to 30.2, the lowest on record, and employment fell to the weakest since Markit started tracking the numbers.
5. Twitter shares fell to an all-time low. The stock fell 5.45% to close at a record low of $29.33. The stock has been sliding since the disappointing earnings call last Tuesday night in which interim CEO Jack Dorsey put out a tepid outlook for user base growth.
6. Coal company Alpha Natural Resources filed for Chapter 11 bankruptcy. The filing gives the company time to reorganize its finances. The coal industry is in turmoil, as natural gas use surges and government regulation pushes demand away from the fuel. "The change and challenges the U.S. coal industry has experienced over the last several years are greater than any in the past three decades," said CEO Kevin Crutchfield in a statement. 

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