I'm developing a Web service using a VM behind a firewall on a University. I need to know what a range of IP address to give to our IT guy so we can get access to calls from foursquare.
You'll never be able to reliably pin this down. It's not as if they are using one subnet.
Your IT guy needs to open up your firewall differently, based on your end, not Foursquare's.
Navigate to zoneedit.com in the DNS lookup field enter foursquare.com and in the dropdown select "Ip Address (A)" you will find only one record listed. After further research I found that Foursquare is hosted at Amazon Web Services and the most likely scenario is that thy will have have multiple servers hosted behind a single IP'ed load balancer. You will need to get the IPs for foursquare.co.uk or any other top level domains it may operate under (COM,NET,CO.UK and so on) but from what I can find CO.UK is the only other country it operates in.
来源：https://stackoverflow.com/questions/9167713/what-is-the-ip-address-range-for-foursquare-api