ArnNotLikeIfExists

compares an ARN in a request to a list of ARN patterns in your policy. The policy values can include asterisks (*) to match multiple characters and question marks (?) to match a single character within an ARN segement. Wildcards cannot be used to span ARN segment, so the partition, service, region, account, and resource must all be present in your policy value, even if they are all wildcards. The comparison is case sensitive.

To match a request, the context key can be absent, but if present it must NOT match any of the ARN patterns in your policy.

You can use policy variables in the value of this operator.

So you know

ArnNotLikeIfExists behaves exactly the same as ArnNotLike. "Negative" operators such as ArnNotLike already match requests when the key is not present, so the IfExists suffix has no effect. There is no harm in adding IfExists — it arguably makes the intent clearer.

ArnNotLikeIfExists in an Allow Statement

Simulate in IAM Simulate

Policy Condition Request Context Result

Policy Condition	Request Context	Result
"ArnNotLikeIfExists": { "aws:PrincipalArn": [ "arn:aws:iam:::role/Admin", "arn:aws:iam:::role/Manager" ] }	`aws:PrincipalArn: null`	✓ Allowed Assuming no explicit Deny elsewhere
"ArnNotLikeIfExists": { "aws:PrincipalArn": [ "arn:aws:iam:::role/Admin", "arn:aws:iam:::role/Manager" ] }	`aws:PrincipalArn: arn:aws:iam::123456789012:user/User`	✓ Allowed Assuming no explicit Deny elsewhere
"ArnNotLikeIfExists": { "aws:PrincipalArn": [ "arn:aws:iam:::role/Admin", "arn:aws:iam:::role/Manager" ] }	`aws:PrincipalArn: arn:aws:iam::123456789012:role/AdminRole`	− Not Allowed Statement does not apply

"ArnNotLikeIfExists": {
  "aws:PrincipalArn": [
    "arn:aws:iam::*:role/Admin*",
    "arn:aws:iam::*:role/Manager*"
  ]
}

aws:PrincipalArn: null

✓ Allowed Assuming no explicit Deny elsewhere

"ArnNotLikeIfExists": {
  "aws:PrincipalArn": [
    "arn:aws:iam::*:role/Admin*",
    "arn:aws:iam::*:role/Manager*"
  ]
}

aws:PrincipalArn: 
    arn:aws:iam::123456789012:user/User

✓ Allowed Assuming no explicit Deny elsewhere

"ArnNotLikeIfExists": {
  "aws:PrincipalArn": [
    "arn:aws:iam::*:role/Admin*",
    "arn:aws:iam::*:role/Manager*"
  ]
}

aws:PrincipalArn: 
    arn:aws:iam::123456789012:role/AdminRole

− Not Allowed Statement does not apply

ArnNotLikeIfExists in a Deny Statement

Simulate in IAM Simulate

Policy Condition Request Context Result

Policy Condition	Request Context	Result
"ArnNotLikeIfExists": { "aws:PrincipalArn": [ "arn:aws:iam:::role/Admin", "arn:aws:iam:::role/Manager" ] }	`aws:PrincipalArn: null`	✕ Denied
"ArnNotLikeIfExists": { "aws:PrincipalArn": [ "arn:aws:iam:::role/Admin", "arn:aws:iam:::role/Manager" ] }	`aws:PrincipalArn: arn:aws:iam::123456789012:user/User`	✕ Denied
"ArnNotLikeIfExists": { "aws:PrincipalArn": [ "arn:aws:iam:::role/Admin", "arn:aws:iam:::role/Manager" ] }	`aws:PrincipalArn: arn:aws:iam::123456789012:role/AdminRole`	− Not Denied May be allowed by another statement

"ArnNotLikeIfExists": {
  "aws:PrincipalArn": [
    "arn:aws:iam::*:role/Admin*",
    "arn:aws:iam::*:role/Manager*"
  ]
}

aws:PrincipalArn: null

✕ Denied

"ArnNotLikeIfExists": {
  "aws:PrincipalArn": [
    "arn:aws:iam::*:role/Admin*",
    "arn:aws:iam::*:role/Manager*"
  ]
}

aws:PrincipalArn: 
    arn:aws:iam::123456789012:user/User

✕ Denied

"ArnNotLikeIfExists": {
  "aws:PrincipalArn": [
    "arn:aws:iam::*:role/Admin*",
    "arn:aws:iam::*:role/Manager*"
  ]
}

aws:PrincipalArn: 
    arn:aws:iam::123456789012:role/AdminRole

− Not Denied May be allowed by another statement

ArnNotLikeIfExists

ArnNotLikeIfExists in an Allow Statement

ArnNotLikeIfExists in a Deny Statement

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