Originally Posted by Happy

There is no such thing called IHG closure forum.

There is an IHG forum on FT just like another other loyalty program of airlines and hotels. Multiple accounts led to closure is being discussed on and off in the past several years. You certainly could find information in IHG forum if you search hard enough. It is not a recent occurrence because people learned this long time ago so nobody is stupid enough to try, knowing how harsh IHG could be, especially since it now aggressively engages in auditing people's accounts on any violation of T&Cs. A friend got her IHG account suspended triggered by getting a second 80K Chase bonus in less than 9 months (during the product switch, she X'ed a new Visa and later got the MC - Chase gave 2nd bonus but IHG flagged the account). Eventually the account was re-activated but not without a 2 weeks audit and almost got a closure because she had used untargeted promo codes on a stay 18 months ago. Luckily she only netted a few thousand K's so not a big offender.

As Beltway aptly posted, why using different account number is NOT in the Wiki - there are reasons for that and such reasons do not need to be spelled out.