Today (Monday 11/20) at 8 PM (Eastern) is the deadline for MLB clubs to file off-season MLB and minor league reserve lists with the MLB office, so the Cubs have just a few hours left to decide which Rule 5 Draft-eligible minor leaguers to add to their MLB 40-man roster in order to prevent the player(s) from being eligible to be selected by another MLB club in the Rule 5 Draft.
The 2017 MLB Rule 5 Draft will be held on the last day of the Winter Meetings (Thursday December 14th).
MLB and minor league reserve lists are used to determine eligibility for selection in the Rule 5 Draft, and once the reserve lists are filed, Rule 5 Draft eligible players on minor league reserve lists are essentially "frozen," meaning the player cannot be added to the MLB 40-man roster, transferred to a different minor league reserve list, traded, or released until the conclusion of the Rule 5 Draft.