When McDonald's first introduced all-day breakfast last fall, many questioned whether it would be a success. The move was meant to curb a years-long decline for the fast food giant, but complaints from franchisees, among other issues, indicated all-day breakfast might not be a savior for the company. Now, it appears the gamble is paying off.

McDonald's sales were up in the fourth quarter of Fiscal Year 2015, and as an added bonus, fast food rivals seem to be losing business to the Golden Arches. When it announced worse-than-expected first-quarter earnings for Fiscal Year 2016 on Wednesday, Jack in the Box made a not-so-subtle reference to McDonald's.

"Jack in the Box sales in the last part of the quarter were lower than we anticipated as several competitors began promoting aggressive value offers," Jack in the Box CEO Lenny Comma said. "We also experienced weakness at breakfast and lunch throughout the quarter, which we attribute primarily to our decision to shift the timing of some of our promotional activity around breakfast to the second quarter as compared to the first quarter of last year. In addition, we believe a competitor's messaging around its launch of all-day breakfast had some impact on our results, particularly in the 10:30 a.m. to noon period."

And it's not just Jack in the Box. Business Insider notes at least one Wall Street analyst thinks Dunkin' Donuts and Bojangles are taking a hit too. Since McDonald's September 1 announcement that it would introduce nationwide all-day breakfast, the company's stock has risen from $93.47 to $116.44 per share. All-day breakfast has been so successful, Mickey D's is considering adding McGriddles to the menu.

Business Insider reports Dunkin sales unexpectedly declined 0.8 percent in the fourth quarter. Bojangles stock is down about 40 percent since its May 2015 IPO.