Alcantara, 22, who hit a solo home run playing for the World Team in the 2013 All-Stars Futures Game, batted .271 with 15 home runs, 69 RBIs and 31 stolen bases at Double-A Tennessee this season, and was batting .196 in 15 games with Licey in the Dominican Republic Winter League.
The second baseman -- ranked No. 8 among Cubs prospects by MLB.com -- earned Southern League midseason and postseason All-Star honors. He ranked second in the Southern League in hits and doubles and was tied for third in stolen bases.
Beeler, 24, was 4-2 with a 3.13 ERA in nine starts for Tennessee. He missed time after he tore a tendon in the middle finger of his right hand, and made six starts in the Arizona Fall League, where he posted a 4-1 record and 2.49 ERA.
In his 15 starts combined, Beeler walked 22 and gave up four home runs over 76 1/3 innings. He started the AFL championship game for the Mesa Solar Sox and gave up one run on two hits over five innings. The right-hander was a 41st-round selection in the 2010 First-Year Player Draft.
Players first signed at age 18 must be added to 40-man rosters within five seasons or they become eligible to be drafted by other organizations through the Rule 5 process. Players signed at 19 years or older have to be protected within four seasons. Clubs pay $50,000 to select a player in the Major League phase of the Rule 5 Draft. If that player doesn't stay on the 25-man roster for the full season, he must be offered back to his former team for $25,000.
In other words, an international player or high school draftee signed in 2009, assuming they were 18 or under as of June 5 of that year, must be protected. A college player taken in the 2010 Draft is in the same boat.
Some of the Cubs' Minor Leaguers who qualify but were not added to the 40-man include pitchers Matt Loosen and Zach Cates and infielders Gioskar Amaya and Marco Hernandez.
The Rule 5 Draft will be held Dec. 12.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.