209.67.38.99    gd17.doubleclick.net    Evil DoubleClick network
204.178.112.170 md1.doubleclick.net     ditto
205.138.3.62    gd11.doubleclick.net    ditto
199.95.207.0/24 doubleclick.net         ditto
199.95.208.0/24 doubleclick.net         ditto
216.52.13.39    ads22.focalink.com      ditto
216.52.13.23    ads22.focalink.com      ditto
207.79.74.222   --unlisted--            R.R. Donnelly (marketing/harvesting)
209.204.128.0/18 Sonic.net              BayTSP Illegal DMCA enforcer/scanner/spider 
                                        (note the mask! 255.255.192.0)
209.122.130.0/24 ska0xxx.erols.com      More of the BayTSP crap

The following list came from a post to sharereactor.com  Most of the following 
address segments are misregistered with ARIN or are subdelegated.  
These blocks are probably bigger than they should be because of the subdelegations.  

Corrections to these addresses are welcomed.

(*) Indicates that the block is probably larger than it should be.  You
may wish to check www.arin.com to decide how big of a block that you want to make.

Most (all probably) ISPs won't give you any customer information so you should probably
block the entire address range unless there is a good reason not to.

216.205.91.0/24 Dellhost.com           Full site scan from this segment, weird registrations
65.174.0.0/16   SPRINTLINK-2-BLKS       OverPeer    subdel to TUMWATER INTERNET FON(*) 
                TUMWATER INTERNET FON-110192230488570 (NET-65-174-0-0-1) 65.174.0.0 - 65.174.1.255
65.160.0.0/23   SPRINTLINK-2-BLKS       OverPear    subdel to RAW HIDE., INC FON
216.122.0.0/16  Lightrealm LR-BLK4      Ranger      subdel HostPro, Inc (*)
                HostPro, Inc HSTPROSEA-NETBLKNAT1 (NET-216-122-0-0-2) 216.122.0.0 - 216.122.0.255
204.92.244.0/24 UUNET-1-A               Ranger      subdel Syndesis, Ltd.
65.192.0.0/24   UUNET65                 MediaForce
65.223.0.0/16   UUNET65                 MediaForce  subdel Obsidian Holdings(*)
                Obsidian Holdings UU-65-223 (NET-65-223-0-0-1) 65.223.0.0 - 65.223.7.255
4.43.96.0/24    MEDIAFORCE-96-13        MediaForce  correct registration!
66.79.0.0/16    Mebtel Communications   MediaDefender(*)
                No further subnet info
64.225.202.0/25 Northwest Link          MediaDefender 
208.225.90.0/24 UUNET1996B              RIAA
12.150.191.0/24 RIAA RECORDIN50-191     RIAA  correct registration!
208.192.0.0/16  UUNET1996B              RIAA  subdel Pathlink Technology(*)
                Pathlink Technology PATHLINK2 (NET-208-192-0-0-2) 208.192.0.0 - 208.192.0.255
63.199.57.96/28 Pac BellPBI-NET-7       MPAA  subdel Phoenix Manufacturing
64.166.187.128/27 Pac Bell PBI-NET-8    MPAA  subdel Valerie Bourne  (what?!?!)
198.70.114.0/24 MPAA NET-MPA-1          MPAA  correct registration! 
209.67.0.0/16   Cable & Wireless        MPAA  subdel Exodus(*)
                No further subnet info
207.155.128.0/17 XO Communications      NetPD(*)
                No further subnet info
128.241.0.0/16  Verio, Inc.             NetPD(*)
                No further subnet info
64.106.170.128/27 DATAPIPE-BLK4         C&DCop subdel Warner DP-64-106-170-128 (Could this be Time/Warner?)
207.155.128.0/17 XO Communications      Vidius(*)
                No further subnet info
64.94.89.0/24   Gator.com               GAIN (spyware)  correct registration!
66.35.247.0/24  Cable & Wireless        GAINCME (spyware)
66.35.229.0/24  Cable & Wireless        GAINCME (spyware)
63.236.32.0/26  Internext Media         Xupiter.com
63.148.99.224/27 Cyveillance            Cyveillance correct registration!
65.118.41.192/27 CYVEILLANCE            Cyveillance correct registration!
12.148.209.192/26 NameProtect           NameProtect (spider domain is: crawler918.com)