Time magazine was first published in New York City on March 3, 1923. In the 1930s, it was noticed that sports figures who appeared on Time‘s cover appeared to be jinxed afterward. Time started a sister publication, Sports Illustrated, in 1954, and the “Sports Illustrated cover jinx” became even more famous than Time‘s. SI’s cover jinx was first mentioned in Sports Illustrated in 1973.
 
The Time “cover jinx” was explained in a 1941 newspaper article (below). The term “cover jinx” appeared in a letter to Time published on January 5, 1942.
 
The financial publication Business Week is often said to have a cover jinx because of the long lead time of its stories. If a cover Business Week story says “sell,” it’s allegedly time to buy; if Business Week says “buy,” it’s time to sell.
 
 
Wikipedia: Time (magazine)
Time (trademarked in capitals as TIME) is an American news magazine. A European edition (Time Europe, formerly known as Time Atlantic) is published from London. Time Europe covers the Middle East, Africa and, since 2003, Latin America. An Asian edition (Time Asia) is based in Hong Kong. As of 2009, Time no longer publishes a Canadian advertiser edition. The South Pacific edition, covering Australia, New Zealand and the Pacific Islands, is based in Sydney.
 
Time is the world’s largest weekly newsmagazine, and has a domestic audience of 20 million and a global audience of 25 million.
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First issue: March 3, 1923
     
Wikipedia: Sports Illustrated
Sports Illustrated is an American sports magazine owned by media conglomerate Time Warner. It has over 3.5 million subscribers and is read by 23 million adults each week, including over 18 million men. It was the first magazine with circulation over one million to win the National Magazine Award for General Excellence twice. Its swimsuit issue, which has been published since 1964, is now an annual publishing event that generates its own television shows, videos and calendars.
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First issue:  August 16, 1954
 
Wikipedia: Sports Illustrated Cover Jinx
The Sports Illustrated Cover Jinx is a myth that states that individuals or teams who appear on the cover of the Sports Illustrated magazine will subsequently be jinxed (experience bad luck).
 
Google News Archive
4 October 1941, Afro-American, pg. 21, col. 6:
Finds Jinx Fails to
Work on Joe Louis
Magazine Superstition Seems to
Click for White Athleted Only
By JOHN JASPER
NEW YORK—If the publication of Joe Louis’s photograph on the front page of Time magazine last week was superstitiously designed to chase him out of the championship, it failed to work.
 
Among athletes it is a legend that when Time prints their pictures on its cover page, they are done for.
 
Cavalcade, the sensational race horse, was going strong until one week Times printed a colored reproduction of Cavalcade on its front page. There was the end of Cavalcade’s winning streak.
 
Bob Feller, Cleveland’s wizard fast-ball pitcher, was the best in the big league. Then Time printed a picture of him in colors, and Feller hurt his arm.
 
Harmon Jinxed
Tommy Harman ofMichigan was an all-American backfield football star, running through one strong opponent after another. Then came Time with its colored photo of Tommy, and on that Saturday Illinois bottled him up all day, and defeated Michigan, although Illinois had not won a game before this all season.
 
Alice Marble won the tennis championship when Time printed a picture of her opponent on its cover.
 
Goodman, the golfer, blazed through all the preliminary matches through the year, and was a certainty to win the national title, until Time stepped in with a colored photograph, and that finished Goodman.
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The sporting world owes a great deal of thanks to Joe Louis, who has broken Time magazine’s jinx. From now on, nobody need be superstitious about it.
 
Time magazine
Letters, Jan. 5, 1942
Monday, Jan. 05, 1942
Cover Jinx
Sirs:
TIME cover jinx still seems to be working. Latest casualties: Husband Kimmel, Fedor von Bock.
J. F. R.
Washington, D.C.
 
> TIME’S “cover jinx” has sometimes appeared to work on sports figures but not on others. Franklin Roosevelt, who has appeared on TIME’S cover six times (including this week) since 1923 has, apparently, never felt it. No jinx operated on Admiral Kimmel or General von Bock: the Admiral was placed on the cover after the news of Pearl Harbor arrived; of the General TIME said in its cover story, “when a list is made of the generals who have done most to whittle down Germany’s chances of victory the name of Bock may lead all the rest.” TIME hopes Admiral Yamamoto may rank as a sports figure.—ED.
   
Time magazine
Publisher’s Letter: Dear TIME-Reader
Monday, Aug. 15, 1955
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Actually, the myth of the TIME sports-cover jinx has never been more than just a myth since it first started back in the ‘30s. As happens to everybody, TIME sports-cover subjects sometimes had tough breaks. In most cases, they went right on setting new records and winning new honors.
   
Sports Illustrated
October 08, 1973
19th Hole: The Readers Take Over
Sirs:
As a Pittsburgh Pirate fan I thoroughly enjoyed your article Churned by the Gut-Grinder (Sept. 24). You have reported the frantic National League East race perfectly. But why did you put Danny Murtaugh on the cover? All year the team or player featured on the cover has proceeded to drop out of the lead in the division or gone on a losing streak. Starting off on April 9 was Steve Carlton, who has had a bad season. Next, on April 30, were the San Francisco Giants, who eventually dropped out of first place. Wilbur Wood was on the June 4 cover and ended up having a losing streak. The hot New York Yankees followed (July 2), and they soon turned cold. Carlton Fisk and the Red Sox (July 30) barely touched first place. Everybody was sure the Dodgers would win a division title this year, but after being on your Aug. 20 cover they lost their big lead. Now we come to the Pirates, who rose out of last place to take over first—but not for long. My poor team lost seven of its next 11.
LEE SIEGEL
Pittsburgh
 
Sirs:
The rumor that any team or athlete appearing on your cover is jinxed was certainly enhanced when Texas, which you so boldly proclaimed No. 1 on your Sept. 10 cover, was defeated in its very first game. Then the next week you turn right around and select the Miami Dolphins, thus breaking their string of victories. Could you arrange a cover story on Navy in late November?
HENRY S. LARSEN JR.
Lieut. Colonel, USA
West Point, N.Y.
 
Google Books
Jim Murray: An Autobiography
By Jim Murray
New York, NY: Macmillan Pub. Co.
1993
Pg. 85: 
One curious outgrowth of the Hogan bus accident (1955—ed.) was that it gave birth to the myth of a Time, Inc. cover jinx. Time magazine had an infelicitous run. It put Hogan on the cover and he nearly lost his life—and career—to a bus accident. They put the prizefighter Sugar Ray Robinson on the cover—and he was one of about three prizefighters who had ever made it—and he promptly lost the first fight of his professional career.  (...) Unreasonably enough, this translated in the public mind into a jinx label on that other Time, Inc., publication, Sports Illustrated.