Year - 2006
Main Brands - Topps, Fleer, Upper Deck
Number of Players Included Among All the Sets: 35
Players Included in Every Set: 13
And then there were three. Donruss baseball bit the dust when MLB decided to not renew their license. Fleer was on life support, too, as it declared bankruptcy in 2005 and was bought by Upper Deck.
The 2005 set was the first Fleer set produced by Upper Deck. It had just 430 cards, much smaller that Topps' 659 cards and Upper Deck's set of 1000. Yes, the UD set had 1000 cards (and another 250 in an update set).
The massive Upper Deck set is the reason for 35 Cubs players among the three sets. You'll see lots of players with just an Upper Deck card.