Yandex.Direct is concerned with the security of ads placed on its service. Therefore, a multistage technology, which combines both automatic and manual filtration methods, is used to protect against unfair and erroneous clicks.
Advertisers are not charged for clicks identified by Yandex.Direct as invalid.
Often an increase in the number of ad clicks can be caused by other factors. The most frequent reasons for spikes in activity are described in the section I noticed a spike (or a dip) in impressions (or clicks or expenditures).