Under the new CBA rules, each pick in the first 10 rounds are assigned a hard slot number by the MLB draft office. For the 2012 draft the #1 pick's slot has been assigned a $7.2M weighting, and each slot after that has a successively smaller amount assigned - down to $125K for the last pick in the 10th round (#300 overall). For each team, the slot assigned to their individual picks is not important, rather it's the sum total of the slots assigned to each of their picks in the top 10 rounds. In other words, a team will not be penalized if they pay a specific draft pick in the first 10 rounds an overslot signing bonus, but it will be penalized if the sum total of all the signing bonuses they pay their top 10 round picks is more than the sum total of all the slot numbers that the MLB draft office assigned to those picks.
The Giants have no comp picks this year, but they do have all of their own picks in each of the first 10 rounds. The sum total that the MLB draft office has assigned to the Giants picks is $4,076,400. Only the Braves, Rays, D'backs, Tigers and Angles have a smaller pool than the Giants. The Tigers (1st round) and Angels (1st and 2nd round) both lost at least their 1st round due to signing a Type A free agent.
BA.com has an article up with the aggregate numbers for all 30 teams, as well as a more in-depth explanation of the rules: