Case Study: Recovering from a Google Algorithm Penalty

The Day Traffic Died

March 15, 2025. A Monday. The client's organic sessions went from 24,000/day to 4,800/day by Wednesday. No manual action in Search Console. But something was clearly wrong.

The client was a mid-market SaaS company that had hired an agency two years prior. That agency built links. A lot of them.

Finding the Root Cause

We ran the domain through Google Search Console's links report. 4,200 referring domains. Then we ran it through Ahrefs. 8,700 referring domains. The gap was suspicious.

Cross-referencing with Majestic and Semrush showed the truth: 6,000+ domains were PBNs (private blog networks). Same IP range, same registrar, same template. The previous agency had built 85% of their link profile on manufactured sites. For a complete history of Google core updates and what triggers them, see our core updates history guide.

The March 2025 core update had Penguin-like link spam filters baked in. Google didn't need to announce it — the traffic graph told the story.

The Recovery Plan

Week 1: Audit and Categorize

We exported every backlink from Ahrefs, Majestic, and GSC. We tagged each as:

• Green: editorial links from real sites (retain)
• Yellow: questionable directories and low-quality but not spammy (keep, monitor)
• Red: PBNs, paid links, exact-match anchor text spam (disavow)

We found 2,300 red domains.

Week 2-3: Outreach for Manual Removals

Before disavowing, we emailed every webmaster on the red list. 90% never replied. 8% said they'd remove the link. Only 2% actually did.

Week 4: The Disavow File

We submitted a disavow file with 2,100 domains and 4,500 specific URLs. We grouped the domains by reason in comments so we could track what worked.

The Wait

Google says disavow processing takes "weeks." It took 12 weeks for us. Traffic stayed flat at 4,800 sessions for the first 10 weeks. Then in week 11, it crept to 6,500. Week 12: 11,200. Week 24: 21,600 — 90% recovery.

What We Learned

1. Never trust an agency that promises "50 backlinks in 30 days." Real links don't scale that way.

2. Disavow in batches. We did all 2,100 at once, but batch processing (500 per week) might have shown results faster.

3. Replace lost links. While waiting, we built 15 genuine editorial links through HARO and guest posting. New content rankings helped the recovery.

The site never fully recovered to 24K sessions — it stabilized at 22K. But considering the alternative was staying at 4.8K, we'll take it. If you're planning a domain migration, our SEO migration guide covers the redirect strategy you need to avoid compounding penalties.

Related Articles

• Google Core Updates: History, Patterns, and Recovery Strategies
• SEO Migration Guide: Changing Domains Without Losing Rankings