Back in January 2015, LinkedIn introduced a “commercial use limit” on search.
On a positive note, it meant that free account-holders could see the full names on 3rd degree profiles, something previously not allowed. But it came at a price. A search limit that, if reached, indicates to LinkedIn that you’re likely using LinkedIn for commercial use.
And for that privilege, they really want you to pay, which is understandable.
You’ve reached the commercial use limit on search
The limit is very hard to actually pinpoint. Some months I get a “You’ve reached the commercial use limit on search” message after a few days, other times it takes far longer. But when you reach the limit, although you’ll still be able to search, your results will be severely limited.
However, all is not lost! I found a brilliant tool that is free to use.
The LinkedIn X-Ray Search Tool allows you to search with no restrictions as it accesses public data available on Google. You can use Boolean logic in the searches, and in my experience with this tool, you get decent results back. There do seem to be differences between the results you would get from LinkedIn itself and LinkedIn X-Ray searches, but not so much as to worry about too much.