Not really qualified to answer this but I also don't know your level of expertise. To me that sounds like a lot if per bureau. You should have an idea which cards pull from which bureau. I think 3 cards from different issuers is a good way to vary the inquiries but you must also consider which bureau they pull from

I thought that the "per bureau" thing only held true for like 24 hours.

I believe I read somewhere that bureaus all forward eachother updates each day. So applying to 3 cards at three different lenders only really works if you do it all in the same day. Is this not the case?

The idea is to spread out inquires between bureaus as they remain on your credit report for up to 25 months. Many people get denied for too many inquires (this applies to when one credit bureau is pulled) so it is helpful to have them divided among the big three if possible. Inquires appear on your report right after you apply, the only good thing about AORs is that your accounts appear and age together. My question to OP would be similar to the one above, is this per bureau or a total?

No correct answer other than to say something absurd like 100 is too many. What is too many for one person (limited history, ding on their credit, etc) might be well within a bank's comfort zone for someone else (30 year history, 1% util rate on plenty of available credit).

As far as I know, inquiries are not shared among bureaus, but once your new account hits your credit reports, it will hit all 3. This reports the account's age, available credit, amount used, etc. But if the issuing bank pulled Experian, for instance, Equifax has no way of knowing exactly when the inquiry for that new credit occurred nor whether the issuing bank pulled Experian or Transunion. They just know the new account exists now. This is why you want to spread the inquiries among them as this minimizes the effect on your credit scores.

The inquiries in my case are total, not per bureau - 4 on Experian, 5 on Equifax, and 2 on Transunion. This raises the question whether CC companies look at the number of inquiries or the number of recently opened accounts. The latter should be the sum of the inquiries across all the reporting agencies, making spreading out the inquiries across bureaus potentially moot.

I don't know how they do it, but given that all the info is there for them to look at it seems kind of silly to just look at the inquiries for that particular bureau. But then again banks have been known to be prone to do silly things.

They look at both # of recent inquiries and new accounts with caution. And don't forget the increasing tendency these days to check the number of Visa/MC applications via ARS and non-major CRAs these days. Even though the hard inquiry is shared across the major agencies, they can still see the consolidated number via ARS. It excludes Amex, Discover and other non Visa/MC apps.

Not all banks use ARS:

Q== Which issuers pull ICS/ARS upon original application for credit (does this make bumpage futile)?
A== FNBO, Infibank, Principal, USBank, ELAN

Q== Which issuers report denials to ICS/ARS?
A== Bank of America, Juniper/Barclays, Wells Fargo

Q== Which issuers pull ICS/ARS for CLI purposes and/or account review purposes?
A== Citi, CHASE, National City

Wow, very interesting and useful information. I read on the Club Carlson CC thread in milebuzz that this CRA can be frozen.

Would you tell me what do you mean "ARS, ICS, CRA" please? Thank you for your help.

In addition to the credit bureaus (that's CRA, btw), the Visa/Master card issuers use these ICS/ARS to verify the applicants' information and number of inquiries. So, pretty much every Visa/Master card reports there. ICS stands for Issuers Clearance House Services. You can freeze ICS just like the credit bureaus.

note that some ARS reports track by household not individual.

This FatWallet thread is an excellent read for the topic. In fact djrez4's list appears to be a partial one.

ICS (Issuers Clearinghouse Service) Disputes and Which Issuers Report Inquiries to ICS - AOR Killer? Inquiry Safehaven

Quite important and relevant for all CC churners/AOR fans.

I applied for the Club Carlson CC from U.S. Bank. I was denied as my Experian was frozen. Since there has not been any hard inquiry by U.S. Bank, will the transaction be reported as DENIAL for Banks to see?

Will it also have the reason why it has been denied.

It is possible to ZERO-OUT your Equifax and Transunion inquiries with a little investment. I posted about it here but there is a lot more information on "credit boards"

What I have also been somewhat successful in doing is locking Experian and requesting banks to pull one of the other two .. this does not work with American Express but I've had success with Citi and BOA which seem to typically pull EX in Northern VA .. other banks like Chase, US Bank, Barclays have been pulling EQ or TU for me anyway which I'm able to clean up after a couple of churns

since some issuers use ARS and other alternative reports in addition to one of the main CRAs, this investment may not have that high of return.