Try adding an escape for the "$" in the curl command.
However the following is tested this on 11.5.4+:
curl -sk -u admin:admin -X GET https://10.3.155.111/mgmt/tm/asm/policies/H7xqtWU5TfZJpeXDcC3xAA/signatures?\$filter=performStaging%20eq%20true\&\$select=name,id,performStaging | jq .
{
"selfLink": "https://localhost/mgmt/tm/asm/policies/H7xqtWU5TfZJpeXDcC3xAA/signatures?$select=name%2Cid%2CperformStaging&$filter=performStaging%20eq%20true",
"kind": "tm:asm:policies:signatures:signaturecollectionstate",
"previousLink": "https://localhost/mgmt/tm/asm/policies/H7xqtWU5TfZJpeXDcC3xAA/signatures?$skip=0&$select=name%2Cid%2CperformStaging&$filter=performStaging%20eq%20true",
"totalItems": 4513,
"nextLink": "https://localhost/mgmt/tm/asm/policies/H7xqtWU5TfZJpeXDcC3xAA/signatures?$skip=0&$select=name%2Cid%2CperformStaging&$filter=performStaging%20eq%20true",
"items": [
{
"selfLink": "https://localhost/mgmt/tm/asm/policies/H7xqtWU5TfZJpeXDcC3xAA/signatures/1p7RmgJSYdJTivPK7b2b6A",
"kind": "tm:asm:policies:signatures:signaturestate",
"performStaging": true,
"id": "1p7RmgJSYdJTivPK7b2b6A"
},
{
"selfLink": "https://localhost/mgmt/tm/asm/policies/H7xqtWU5TfZJpeXDcC3xAA/signatures/7TlZ3m1ho4uFZKhO10RVlQ",
"kind": "tm:asm:policies:signatures:signaturestate",
"performStaging": true,
"id": "7TlZ3m1ho4uFZKhO10RVlQ"
}
...
Filtering for "false", then "true" and again without escaping the "$":
curl -sk -u admin:admin -X GET https://10.3.155.111/mgmt/tm/asm/policies/H7xqtWU5TfZJpeXDcC3xAA/signatures?\$filter=performStaging%20eq%20false | jq .items[].performStaging | wc -l
0
curl -sk -u admin:admin -X GET https://10.3.155.111/mgmt/tm/asm/policies/H7xqtWU5TfZJpeXDcC3xAA/signatures?\$filter=performStaging%20eq%20true | jq .items[].performStaging | wc -l
4513
curl -sk -u admin:admin -X GET https://10.3.155.111/mgmt/tm/asm/policies/H7xqtWU5TfZJpeXDcC3xAA/signatures?$filter=performStaging%20eq%20false | jq .items[].performStaging | wc -l
4513
Reference questions which cover similar issues:
<this linked content has been deleted>
https://devcentral.f5.com/s/feed/0D51T00006n5aqRSAQ