Here are five things you must know for Monday, Oct. 15:

1. -- Sears Declares Bankruptcy

Sears Holdings Corp. (SHLD)  finally succumbed to what long seemed inevitable: The storied retailer filed for Chapter 11 bankruptcy protection in the early morning hours on Monday, Oct. 15.

The filing for the Hoffman Estates, Ill.-based department store owner comes ahead of a looming debt repayment due later Monday and just after the chain added restructuring expert Alan J. Carr to its board. It reportedly had started missing payments to vendors, sparking concerns about its future.

Sears shares have plummeted this year, closing at 40 cents on Friday, Oct. 12. In premarket trading on Monday, the stock was down 27.5% to 29 cents. Sears started 2018 above $3.50 and was above $6.20 in October 2017.

Sears said it will close 142 unprofitable stores near the end of the year, which are in addition to the previously announced closings of 46 unprofitable stores that are expected to be completed by November. It also said it reached a deal with its lenders that will allow hundreds of its stores to remain open for now.

The retailer said its controlling shareholder, Edward Lampert, has stepped down as CEO, but will remain chairman. The company said it created an Office of the CEO that will run day-to-day operations during the bankruptcy process.

2. -- Stock Futures Sink Amid Tensions Between the U.S. and Saudi Arabia

U.S. stock futures were falling slightly on Monday, Oct. 15, amid escalating tensions between the U.S. and Saudi Arabia over the death of a prominent Saudi journalist in Turkey last month as well as renewed concerns for trade disputes between the U.S. and its major economic partners.

Jamal Khashoggi's disappearance last week, following a visit to the Saudi consulate in Istanbul on Sept. 28, has sparked both an international murder investigation and a sharp response from the White House, with Donald Trump threatening "severe" consequences if the Saudi government was to be found responsible. Khashoggi is a columnist for the Washington Post.

The tensions slammed shares in Riyadh on Monday, with the benchmark Tadawul All Share Index falling more than 3.5%. The turmoil also sent crude oil prices higher following last week's selloff amid a wild week on Wall Street.

Contracts tied to the Dow Jones Industrial Average declined 3 points, futures for the S&P 500 fell 1.15 points, and Nasdaq futures were down 14 points.

Stocks in Asia fell sharply Monday after also being rattled by the tensions, as well as comments from U.S. Treasury Secretary Steven Mnuchin, who told the International Monetary Fund's annual meeting in Bali that his department would like to use language to prevent current manipulation into any new U.S. trade deals.

The comments hit markets in Japan, which is currently negotiating a new agreement with the United States. Tokyo's Nikkei 225 tumbled 1.87%.

3.  -- Bank of America Earnings, Retail Sales Highlight Monday's Calendar

Bank of America Corp. (BAC)  earned 66 cents a share in the third quarter, 4 cents above analysts' estimates. The stock rose 0.8% in premarket trading.

J.B. Hunt Transport Services Inc. (JBHT) and Charles Schwab Corp. (SCHW)  also are scheduled to post results on Monday.

The economic calendar in the U.S. on Monday includes Retail Sales for September at 8:30 a.m. ET, the Empire State Manufacturing Survey for October at 8:30 a.m., and Business Inventories for August at 10 a.m.

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4. -- Defense Companies Harris Corp. and L3 Technologies to Merge

Defense companies Harris Corp. (HRS)  and L3 Technologies Inc. (LLL) agreed to merge, creating the sixth-largest defense contractor in the U.S. with a market value of about $34 billion.

The all-stock deal values L3 at $15.7 billion, slightly above its market capitalization on Friday of $15.3 billion. Harris has a market capitalization of $18.2 billion. Under the deal, Harris shareholders will own about 54% of the combined company -- L3 Harris Technologies Inc. -- with L3 shareholders owning the rest.

The deal comes amid increased military spending from the Trump administration.

"We are in an environment where the economy is pretty strong, we know defense spending is coming up, the 2019 (federal) budget is up 3% over 2018, 2018 was up 9% to 10% over the prior year," Harris CEO Executive William Brown told Reuters in an interview.

"I think there is an increasing need for more investment, more end-to-end solutions," Brown added.

The merger is expected to close during the middle of 2019.

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5. -- Legal Weed Is Seen as a $200 Billion Industry

Executives at cannabis company Canopy Growth Corp. (CGC)  and its partner, Constellation Brands Inc. (STZ) , said legal-weed products eventually will be at least a $200 billion segment -- and could even disrupt $500 billion of businesses across multiple sectors.

"Our view is that in the next 10+ years, this is going to be a $200 billion business worldwide. And some would argue [that's] understating the case," Constellation Chief Operating Officer Bill Newlands said Saturday, Oct. 13, at Jim Cramer's Boot Camp for Investors in New York. 

Constellation, which owns alcoholic-drink brands like Corona beer and Robert Mondavi wines, recently paid $4 billion to boost its stake in Canopy Growth to 38%. The company also purchased warrants giving it the option to increase that to a majority stake in the future. 

"If you said 10 years ago: 'Would we be right here having this discussion today?,' we all would have said, 'no, we wouldn't have been,'" Newlands told Cramer. "But the market's moving, the consumer perception is moving and in our judgment, this is going to happen. [Cannabis] is going to be legal in most countries that matter around the world in a relatively short period of time."

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