Wall Street closed lower on Wednesday, after weaker-than-expected corporate earnings from Caterpillar Inc. weighed on investor sentiment.

Caterpillar Inc. (NYSE: CAT) reported a disappointing fiscal third-quarter profit on mining weakness, as the company issued earnings of $946 million, or $1.45 a share, compared with $1.7 billion, or $2.54 a share, a year ago. Analysts had expected earnings of $1.66 a share, according to Reuters. Revenue fell 18 percent to $13.4 billion. On Wednesday, Caterpillar fell 6.07 percent to close at $83.76 per share.

After the closing bell, AT&T Inc. (NYSE: T) reported fiscal third-quarter earnings excluding items of 66 cents per share on revenue of  $32.16 billion, compared with earnings of 62 cents on revenue of $31.46 billion during the same quarter a year earlier. Wall Street had expected earnings of 65 cents per share on revenue of $32.19, according to Reuters.

During the quarter, AT&T added nearly 1 million subscribers and the company sold a third-quarter record of more than 6.7 million smartphones. In addition, the telecom giant said U-verse had its first billion-dollar revenue month, up 28.1 percent, and total subscribers topped 10 million.

“We’re setting the standard for 4G LTE speeds and network reliability. Our fiber and U-verse expansion projects are ahead of schedule bringing high-speed broadband to millions more customers,” said Randall Stephenson, AT&T chairman and CEO. “With these initiatives, we’re seeing excellent growth across our major platforms -- mobility, U-verse and strategic business services.”

Over the weekend, AT&T agreed to a $4.85 billion tower deal with Crown Castle International Corp. (NYSE: CCI), which includes leasing or selling 9,700 towers to Crown Castle.

On Wednesday, shares of AT&T initially rose on the news, but then edged down 0.06 percent to $35.26 in after-hours trading.

Also after the bell, Akamai Technologies, Inc. (NASDAQ: AKAM) beat Wall Street forecasts and issued a fiscal third-quarter profit of $80 million, or 44 cents a share, on $396 million in revenue, compared with earnings of $48.2 million, or 27 cents a share, on revenue of $345.3 million in the year-ago quarter. Excluding items, Akamai earned 50 cents per share. Wall Street had expected the company to report earnings of 46 cents a share on revenue of $388 million.

"Akamai's strong third quarter and year-to-date financial performance highlights our ability to deliver innovative solutions to leading enterprises globally," said Tom Leighton, CEO of Akamai. "We intend to continue to invest in the business, while also effectively managing the cost and efficiency of our network, to help our customers capitalize on the opportunities enabled by the hyperconnected world."

The company also said its board of directors authorized a new $750 million stock repurchase program.

Shares of Akamai tumbled 7.46 percent to $48.00 after the closing bell.

E-Trade Financial Corporation (NASDAQ: ETFC) said fiscal third-quarter net income came in at $47 million, or 16 cents per share, on revenue of $417 million, compared with a net loss of $29 million, or a 10 cent per share loss in the third quarter of 2012. Earnings per share came in line with Wall Street estimates, while revenue came in just shy of analysts’ expectations.

In addition, the company announced it has entered into a definitive agreement to sell its market making business, G1 Execution Services, to an affiliate of Susquehanna International Group, LLP for $75 million. The transaction is subject to regulatory approvals and is expected to close in three to six months.

“Our core business delivered solid performance in the third quarter as customers continued to engage, with DARTs up 13 percent over the year-ago quarter and customer margin at a five-year high,” said CEO Paul Idzik. “Our consolidated results benefited from the ongoing improvement to the Company’s risk profile, which contributed to our ability to distribute capital from the Bank to the Parent this quarter -- a significant milestone for E*TRADE. Finally, we are pleased to strike a deal to sell our market maker that will serve our customers and shareholders well, and allow Management to concentrate our time and attention on the core business and our customers.”

E-Trade shares fell 3.92 percent to $16.66 in extended-hours trading.

Ahead on Thursday’s earnings calendar, notable companies reporting quarterly results include Microsoft Corporation (Nasdaq: MSFT), Ford Motor Company (NYSE: F), Amazon.com, Inc. (Nasdaq: AMZN), Zynga Inc. (Nasdaq: ZNGA), 3M Co (NYSE: MMM), Xerox Corp. (NYSE: XRX), Colgate-Palmolive Co. (NYSE: CL), The Dow Chemical Company (NYSE: DOW) and Western Digital Corp. (Nasdaq: WDC).

The Dow Jones industrial average fell 54.33 points, or 0.35 percent, to close at 15,413.33. The S&P 500 Index was down 8.29 points, or 0.47 percent, to end at 1,746.36. The Nasdaq Composite Index was down 22.49 points, or 0.57 percent, to finish at 3,907.07.