12.151.229.0/24

ip:	12.151.229.0 
loc:	United States, Chicago (Illinois)  
isp:	AS10584 TradeWeb, LLC » Acc-tradeweb Markets LLC » AT&T Enterprises 2351.381 ms
route:	12.151.229.0/24, ACC-TRAD126-228 - ACC-TRADEWEB MARKETS LLC, US (Chicago (Near South Side)) ... 
reg:	12.0.0.0/8, US, ARIN, 1983-08-23
asn:	AS10584 - TRADEWEB TradeWeb LLC, US
addr:	  350 E CERMAK RD CHGO IL 60616 US

see also:
   12.0.0.0/8       AS7018   NET12 American Registry for Internet Numbers, US
   12.128.0.0/9     AS7018   NET12 American Registry for Internet Numbers, US