Here are five things you must know for Thursday, Aug. 23:

1. -- Stocks Flat as U.S. and China Announce New Tariffs

U.S. stock futures were flat to slightly higher on Thursday, Aug. 23, as the U.S. and China applied tit-for-tat tariffs amid a continuation of trade talks.

Contracts tied to the Dow Jones Industrial Average (^DJI)  rose 10 points, futures for the S&P 500 (^GSPC)  were up 1.25 points, and Nasdaq (^IXIC) futures were flat.

Stocks ended mixed on Wednesday, Aug. 22, after minutes from the Federal Reserve's last meeting on July 31-Aug. 1 indicated central bank officials saw signs that wages were poised to accelerate, lending credence to the Fed's push to raise rates to head off a surge in inflation.

Despite the mixed finish on Wednesday, stocks set a record for the longest bull market run in history, turning 3,453 days old. It eclipsed the previous record set in the 1990s, which ended with the dot-com bust.

The U.S. and China imposed fresh tariffs on $16 billion of each other's goods. The 25% duties included automobiles and metal scrap from the United States and Chinese-made factory machinery and electronic components.

China said Thursday it would lodge a complaint on the new U.S. tariffs to the World Trade Organization.

2. -- Jackson Hole Conference Begins, Alibaba Reports Earnings

The economic calendar in the U.S. on Thursday includes weekly Jobless Claims at 8:30 a.m. ET, the FHFA House Price Index for June at 9 a.m., the PMI Composite FLASH for August at 9:45 a.m., and New Home Sales for July at 10 a.m.

The three-day annual conference of central bankers in Jackson Hole, Wyoming, begins on Thursday. Federal Reserve Chair Jerome Powell will speak on Friday, Aug. 24.

Alibaba Group Holding Ltd. (BABA) - Get Report  reported fiscal first-quarter adjusted earnings of $1.22 a share, beating estimates by 1 cent. Revenue in the first quarter jumped 61%. Shares rose 3.5%.

Hormel Foods Corp. (HRL) - Get Report fell 4.3% in premarket trading on Thursday after the company reported fiscal third-quarter earnings in line with estimates but sales that came up short. The branded foods company cut its sales outlook for 2018.

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3. -- Facebook Pulls Data-Security App From Apple Store

Facebook Inc. (FB) - Get Report pulled its data-security app from Apple Inc.'s (AAPL) - Get Report app store after the iPhone maker ruled that the service violated its data-collection policies, The Wall Street Journal reported, citing a person familiar with the matter.

The app, called Onavo Protect, has been available as a free download through Apple's app store for years, with updates regularly approved by Apple's app-review board, according to the Journal.

"We work hard to protect user privacy and data security throughout the Apple ecosystem," an Apple spokesman said. "With the latest update to our guidelines, we made it explicitly clear that apps should not collect information about which other apps are installed on a user's device for the purposes of analytics or advertising/marketing and must make it clear what user data will be collected and how it will be used."

The app won't disappear from the phones of users who already downloaded it, but Facebook will no longer be able to push updates of the app. Onavo will still be available on Android devices, the person told the Journal.

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4. -- Saudi Arabia Says It Hasn't Scrapped Aramco IPO

Saudi Arabia's energy minister on Thursday denied reports that the kingdom had abandoned plans for a public listing of Saudi Arabian Oil Co., known as Aramco.

"The government remains committed to the IPO of Saudi Aramco at a time of its own choosing when conditions are optimum," said Khalid Al Falih, minister of Energy, Industry and Mineral Resources and chairman of Saudi Aramco. "This timing will depend on multiple factors, including favorable market conditions."

The energy minister added that Aramco had completed its own preparations for the initial public offering.

The comments came after Reuters reported that the IPO -- which would be the largest ever -- had been cancelled and that advisers working on the proposed listing had been disbanded. The article, which cited "four senior industry sources," claimed that the decision to abandon the sale was taken months ago and recent announcements of delays would eventually give way to an admission that the sale had been shelved.

5. -- L Brands Tumbles, Williams-Sonoma Soars

L Brands Inc. (LB) - Get Report was down 5.8% in premarket trading on Thursday after second-quarter earnings from the parent company of Victoria's Secret beat analystss' expectations but the company cut its fiscal-year profit outlook.

Shares of Williams-Sonoma Inc. (WSM) - Get Reportrose more than 7% in premarket trading after second-quarter earnings and sales topped Wall Street estimates and the seller of cookware and home furnishings issued strong guidance for its fiscal third quarter.