We had some client PPC campaigns have inactive keywords but still they get impressions and clicks so what causes this, Most of the time this is caused when the keyword is inactive in search but still active in partner networks. Google has a range of partner sites which serve google results for their clients. GOogle's adwords campaign also serves sponsored results to these sites most probably keywords show impressions and clicks because of this. Though keywords are inactive in google search they are served in Google partner sites.
Other possible reason according to a Google Adwords support guy is that Due to various changes in bidding keywords jump between inactive and active status. Say suppose a advertise run out of funds then if our bid is low and the keyword is inactive it might get activated since the Competitor ads stop showing up. Similiarly if some high bidders reduce their Maximum bid or stop their keywords / campaign then the keywords even if they are low bidding and inactive will start showing up. A keyword will jump from Active to inactive and inactive to active if any ofthe above happens. This is an other reason keywords still has impressions / clicks even if they show inactive status

PPC Management TEAM ( Search Engine Genie )

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