Facing an issue with YARA L rule

[asinghz297]

rule critical_ioc_detected_ip {

  meta:

    author = "Anurag Singh"

    description = "Rule to check for any traffic coming from suspicious IPs related to known IOCs."

  events:

    $e.metadata.vendor_name = "Check Point" or $e.metadata.vendor_name = "Fortinet"

    $e.metadata.product_name = "VPN-1 & FireWall-1" or $e.metadata.product_name = "Fortigate"

    $e.metadata.event_type = "NETWORK_CONNECTION" or ($e.metadata.event_type = "NETWORK_HTTP")

    $e.principal.ip = $sourceip and $e.target.ip = $destinationip

    $kasperskyti.principal.ip[0] = $sourceip or $kasperskyti.principal.ip[0] = $destinationip

    $kasperskyti.metadata.vendor_name = "IOC" and $kasperskyti.metadata.product_name = "IP"

    $ioc = $kasperskyti.metadata.product_event_type

  match:

    $sourceip over 10m

  condition:

    $e and $kasperskyti

}


So I have written this rule to check if there is connection with known IOCs. 
But I am facing an error which says 

validating intermediate representation: event variables are not all joined by equalities, the joined groups are: (e), (kasperskyti)

Can someone help me out in this. 

[raybrian]

rule critical_ioc_detected_ip {

meta:
author = "Anurag Singh"
description = "Rule to check for any traffic coming from suspicious IPs related to known IOCs."
reference_sets = "kasperskyti"

events:
$e.metadata.vendor_name = "Check Point" or $e.metadata.vendor_name = "Fortinet"
$e.metadata.product_name = "VPN-1 & FireWall-1" or $e.metadata.product_name = "Fortigate"
$e.metadata.event_type = "NETWORK_CONNECTION" or $e.metadata.event_type = "NETWORK_HTTP"
$e.principal.ip = $match_ip
$e.target.ip = $match_ip

$kasperskyti.principal.ip[0] = $match_ip
$kasperskyti.metadata.product_name = "IP"
$ioc_severity = $kasperskyti.metadata.product_event_type

match:
$match_ip over 10m

condition:
$e and $kasperskyti
}