PCE: Cleaning a Japanese Keyword Hack From Google

PCE is an engineering consultancy with more than 30 years of experience in infrastructure, construction management and project supervision across the Middle East. Its old WordPress site had been hit by the Japanese keyword hack: in the last seven weeks of 2025, 83% of the site's search impressions came from planted Japanese spam pages, and Japan brought more impressions than any other country although PCE does not target that market.

From the start of 2026 HBS mapped every planted URL pattern in Search Console, replaced the hacked site with a new Next.js website and dashboard, and made every planted URL return 410 (removed permanently). Old WordPress pages with a match on the new site now open the new page. On 24 May 2026 we submitted a clean sitemap with 83 pages, added canonical tags and structured data, and tracked the planted URLs with a custom filter until they were gone.

The last impression for a planted page was on 20 March 2026. Comparing 11 November to 31 December 2025 with 1 April to 30 September 2026: the share of impressions from planted pages fell from 83% to 0%, real impressions per day rose from 52 to 98, daily clicks to real pages rose 51% (from 4.9 to 7.5), and the click-through rate went from 2.1% to 7.6%. All figures come from PCE's own Google Search Console account.