In CA it's definitely Experian only, my credit inquiries showed Chase only on my experian report, today I applied for Chase Freedom Card with score of 712 with lots of lates from defaulted loans that show "paid as agreed" now and got approved with $500 credit limit! Woo hoo!
No, it's not definitely Experian only. Chase pull both EX and EQ in CA. Might depend on North vs South CA though. In the Bay Area they pull both.
EX and EQ here in Northern California, but any really based on income, which card etc.
By the way, it looks like all but the west coast has gone to sleep!
Old thread, but still valuable info. Just bear in mind that the results on the first two pages might not be in line with what Chase is doing currently.
As of earlier this year -- 2013 -- Chase pulled EQ for me, and I'm in Florida.
They pulled EX and I am in HI